21013145128 has 16 divisors (see below), whose sum is σ = 39700409760. Its totient is φ = 10426369200.

The previous prime is 21013145081. The next prime is 21013145149. The reversal of 21013145128 is 82154131012.

It is a junction number, because it is equal to n+sod(n) for n = 21013145096 and 21013145105.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10024308 + ... + 10026403.

It is an arithmetic number, because the mean of its divisors is an integer number (2481275610).

Almost surely, 2^21013145128 is an apocalyptic number.

It is an amenable number.

21013145128 is a deficient number, since it is larger than the sum of its proper divisors (18687264632).

21013145128 is a wasteful number, since it uses less digits than its factorization.

21013145128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20050848 (or 20050844 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The spelling of 21013145128 in words is "twenty-one billion, thirteen million, one hundred forty-five thousand, one hundred twenty-eight".