1961917440 has 352 divisors, whose sum is σ = 7300813824. Its totient is φ = 440401920.

The previous prime is 1961917427. The next prime is 1961917469. The reversal of 1961917440 is 447191691.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1961917392 and 1961917401.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7633792 + ... + 7634048.

Almost surely, 2^1961917440 is an apocalyptic number.

1961917440 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 1961917440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3650406912).

1961917440 is an abundant number, since it is smaller than the sum of its proper divisors (5338896384).

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

1961917440 is a wasteful number, since it uses less digits than its factorization.

1961917440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363 (or 345 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 42.

The square root of 1961917440 is about 44293.5372261011. The cubic root of 1961917440 is about 1251.8729128896.

The spelling of 1961917440 in words is "one billion, nine hundred sixty-one million, nine hundred seventeen thousand, four hundred forty".