21017545372 has 12 divisors (see below), whose sum is σ = 36880926880. Its totient is φ = 10480137696.

The previous prime is 21017545319. The next prime is 21017545387. The reversal of 21017545372 is 27354571012.

It is a congruent number.

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, 7157097 + ... + 7160032.

Almost surely, 2^21017545372 is an apocalyptic number.

It is an amenable number.

21017545372 is a deficient number, since it is larger than the sum of its proper divisors (15863381508).

21017545372 is a wasteful number, since it uses less digits than its factorization.

21017545372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14317500 (or 14317498 counting only the distinct ones).

The product of its (nonzero) digits is 58800, while the sum is 37.

The spelling of 21017545372 in words is "twenty-one billion, seventeen million, five hundred forty-five thousand, three hundred seventy-two".