21202657616 has 40 divisors (see below), whose sum is σ = 47004908160. Its totient is φ = 9075982464.

The previous prime is 21202657613. The next prime is 21202657627. The reversal of 21202657616 is 61675620212.

It is a self number, because there is not a number n which added to its sum of digits gives 21202657616.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21202657613) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18851 + ... + 206786.

It is an arithmetic number, because the mean of its divisors is an integer number (1175122704).

Almost surely, 2^21202657616 is an apocalyptic number.

It is an amenable number.

21202657616 is an abundant number, since it is smaller than the sum of its proper divisors (25802250544).

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

21202657616 is a wasteful number, since it uses less digits than its factorization.

21202657616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226491 (or 226485 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 38.

The spelling of 21202657616 in words is "twenty-one billion, two hundred two million, six hundred fifty-seven thousand, six hundred sixteen".