64512530373021 has 4 divisors (see below), whose sum is σ = 86016707164032. Its totient is φ = 43008353582012.

The previous prime is 64512530373007. The next prime is 64512530373029. The reversal of 64512530373021 is 12037303521546.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64512530373021 - 2¹⁷ = 64512530241949 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64512530373029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10752088395501 + ... + 10752088395506.

It is an arithmetic number, because the mean of its divisors is an integer number (21504176791008).

Almost surely, 2^{64512530373021} is an apocalyptic number.

It is an amenable number.

64512530373021 is a deficient number, since it is larger than the sum of its proper divisors (21504176791011).

64512530373021 is a wasteful number, since it uses less digits than its factorization.

64512530373021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21504176791010.

The product of its (nonzero) digits is 453600, while the sum is 42.

Adding to 64512530373021 its reverse (12037303521546), we get a palindrome (76549833894567).

The spelling of 64512530373021 in words is "sixty-four trillion, five hundred twelve billion, five hundred thirty million, three hundred seventy-three thousand, twenty-one".