1981416640 has 224 divisors, whose sum is σ = 5809878144. Its totient is φ = 628162560.

The previous prime is 1981416631. The next prime is 1981416641. The reversal of 1981416640 is 466141891.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-3 number, since 3×1981416640³ (a number of 29 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 1981416593 and 1981416602.

It is not an unprimeable number, because it can be changed into a prime (1981416641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2322454 + ... + 2323306.

It is an arithmetic number, because the mean of its divisors is an integer number (25936956).

Almost surely, 2^1981416640 is an apocalyptic number.

1981416640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1981416640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2904939072).

1981416640 is an abundant number, since it is smaller than the sum of its proper divisors (3828461504).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1981416640 is a wasteful number, since it uses less digits than its factorization.

1981416640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 955 (or 945 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 40.

The square root of 1981416640 is about 44513.1063845245. The cubic root of 1981416640 is about 1256.0066398556.

The spelling of 1981416640 in words is "one billion, nine hundred eighty-one million, four hundred sixteen thousand, six hundred forty".