1901968640 has 144 divisors (see below), whose sum is σ = 5352794496. Its totient is φ = 638361600.

The previous prime is 1901968591. The next prime is 1901968643. The reversal of 1901968640 is 468691091.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 1901968591 and 1901968600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1901968643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 177845 + ... + 188235.

It is an arithmetic number, because the mean of its divisors is an integer number (37172184).

Almost surely, 2^1901968640 is an apocalyptic number.

1901968640 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 1901968640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2676397248).

1901968640 is an abundant number, since it is smaller than the sum of its proper divisors (3450825856).

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

1901968640 is a wasteful number, since it uses less digits than its factorization.

1901968640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10436 (or 10422 counting only the distinct ones).

The product of its (nonzero) digits is 93312, while the sum is 44.

The square root of 1901968640 is about 43611.5654385394. The cubic root of 1901968640 is about 1238.9899509821.

The spelling of 1901968640 in words is "one billion, nine hundred one million, nine hundred sixty-eight thousand, six hundred forty".