21640645151001 has 64 divisors (see below), whose sum is σ = 32414500339200. Its totient is φ = 14268707601408.

The previous prime is 21640645150991. The next prime is 21640645151011. The reversal of 21640645151001 is 10015154604612.

21640645151001 is a `hidden beast` number, since 2 + 1 + 6 + 4 + 0 + 645 + 1 + 5 + 1 + 0 + 0 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (21640645150991) and next prime (21640645151011).

It is a de Polignac number, because none of the positive numbers 2^k-21640645151001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21640645151011) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 786089805 + ... + 786117333.

It is an arithmetic number, because the mean of its divisors is an integer number (506476567800).

Almost surely, 2^{21640645151001} is an apocalyptic number.

It is an amenable number.

21640645151001 is a deficient number, since it is larger than the sum of its proper divisors (10773855188199).

21640645151001 is a wasteful number, since it uses less digits than its factorization.

21640645151001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28575 (or 28569 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 36.

Adding to 21640645151001 its reverse (10015154604612), we get a palindrome (31655799755613).

The spelling of 21640645151001 in words is "twenty-one trillion, six hundred forty billion, six hundred forty-five million, one hundred fifty-one thousand, one".