21624212016605 has 48 divisors (see below), whose sum is σ = 30205398590640. Its totient is φ = 14799105361920.

The previous prime is 21624212016593. The next prime is 21624212016677. The reversal of 21624212016605 is 50661021242612.

It can be written as a sum of positive squares in 8 ways, for example, as 1700861997241 + 19923350019364 = 1304171^2 + 4463558^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21624212016605 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 61916411 + ... + 62264679.

It is an arithmetic number, because the mean of its divisors is an integer number (629279137305).

Almost surely, 2^{21624212016605} is an apocalyptic number.

It is an amenable number.

21624212016605 is a deficient number, since it is larger than the sum of its proper divisors (8581186574035).

21624212016605 is a wasteful number, since it uses less digits than its factorization.

21624212016605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354350 (or 354339 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 38.

The spelling of 21624212016605 in words is "twenty-one trillion, six hundred twenty-four billion, two hundred twelve million, sixteen thousand, six hundred five".