21624116365 has 32 divisors (see below), whose sum is σ = 28485665280. Its totient is φ = 15685469184.

The previous prime is 21624116357. The next prime is 21624116407. The reversal of 21624116365 is 56361142612.

It is a cyclic number.

It is not a de Polignac number, because 21624116365 - 2³ = 21624116357 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1131822 + ... + 1150768.

It is an arithmetic number, because the mean of its divisors is an integer number (890177040).

Almost surely, 2^21624116365 is an apocalyptic number.

It is an amenable number.

21624116365 is a deficient number, since it is larger than the sum of its proper divisors (6861548915).

21624116365 is a wasteful number, since it uses less digits than its factorization.

21624116365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19461.

The product of its digits is 51840, while the sum is 37.

Adding to 21624116365 its reverse (56361142612), we get a palindrome (77985258977).

The spelling of 21624116365 in words is "twenty-one billion, six hundred twenty-four million, one hundred sixteen thousand, three hundred sixty-five".