15738891021 has 24 divisors (see below), whose sum is σ = 26683872384. Its totient is φ = 8750579040.

The previous prime is 15738891017. The next prime is 15738891059. The reversal of 15738891021 is 12019883751.

15738891021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 15738891021 - 2² = 15738891017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15738891121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3373665 + ... + 3378326.

It is an arithmetic number, because the mean of its divisors is an integer number (1111828016).

Almost surely, 2^15738891021 is an apocalyptic number.

It is an amenable number.

15738891021 is a deficient number, since it is larger than the sum of its proper divisors (10944981363).

15738891021 is a wasteful number, since it uses less digits than its factorization.

15738891021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6752041 (or 6752038 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 45.

The spelling of 15738891021 in words is "fifteen billion, seven hundred thirty-eight million, eight hundred ninety-one thousand, twenty-one".