21609960625 has 40 divisors (see below), whose sum is σ = 29600299872. Its totient is φ = 15640800000.

The previous prime is 21609960611. The next prime is 21609960649. The reversal of 21609960625 is 52606990612.

It is not a de Polignac number, because 21609960625 - 2⁷ = 21609960497 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1443177 + ... + 1458073.

Almost surely, 2^21609960625 is an apocalyptic number.

21609960625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21609960625 is a deficient number, since it is larger than the sum of its proper divisors (7990339247).

21609960625 is a wasteful number, since it uses less digits than its factorization.

21609960625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15139 (or 15124 counting only the distinct ones).

The product of its (nonzero) digits is 349920, while the sum is 46.

The spelling of 21609960625 in words is "twenty-one billion, six hundred nine million, nine hundred sixty thousand, six hundred twenty-five".