64633643251 has 16 divisors (see below), whose sum is σ = 68723668800. Its totient is φ = 60670366848.

The previous prime is 64633643203. The next prime is 64633643299. The reversal of 64633643251 is 15234633646.

It is an interprime number because it is at equal distance from previous prime (64633643203) and next prime (64633643299).

It is a cyclic number.

It is not a de Polignac number, because 64633643251 - 2⁹ = 64633642739 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 64633643198 and 64633643207.

It is not an unprimeable number, because it can be changed into a prime (64633643651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1375005 + ... + 1421233.

It is an arithmetic number, because the mean of its divisors is an integer number (4295229300).

Almost surely, 2^64633643251 is an apocalyptic number.

64633643251 is a deficient number, since it is larger than the sum of its proper divisors (4090025549).

64633643251 is a wasteful number, since it uses less digits than its factorization.

64633643251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47598.

The product of its digits is 933120, while the sum is 43.

The spelling of 64633643251 in words is "sixty-four billion, six hundred thirty-three million, six hundred forty-three thousand, two hundred fifty-one".