21120550616 has 16 divisors (see below), whose sum is σ = 43201126440. Its totient is φ = 9600250240.

The previous prime is 21120550601. The next prime is 21120550639. The reversal of 21120550616 is 61605502112.

It is a happy number.

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, 120003041 + ... + 120003216.

Almost surely, 2^21120550616 is an apocalyptic number.

It is an amenable number.

21120550616 is an abundant number, since it is smaller than the sum of its proper divisors (22080575824).

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

21120550616 is a wasteful number, since it uses less digits than its factorization.

21120550616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240006274 (or 240006270 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 29.

The spelling of 21120550616 in words is "twenty-one billion, one hundred twenty million, five hundred fifty thousand, six hundred sixteen".