64696251 has 4 divisors (see below), whose sum is σ = 86261672. Its totient is φ = 43130832.

The previous prime is 64696243. The next prime is 64696253. The reversal of 64696251 is 15269646.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 64696251 - 2³ = 64696243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64696253) 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 3 ways as a sum of consecutive naturals, for example, 10782706 + ... + 10782711.

It is an arithmetic number, because the mean of its divisors is an integer number (21565418).

Almost surely, 2^64696251 is an apocalyptic number.

64696251 is a deficient number, since it is larger than the sum of its proper divisors (21565421).

64696251 is a wasteful number, since it uses less digits than its factorization.

64696251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21565420.

The product of its digits is 77760, while the sum is 39.

The square root of 64696251 is about 8043.3979759801. The cubic root of 64696251 is about 401.4452944370.

It can be divided in two parts, 6469 and 6251, that added together give a triangular number (12720 = T₁₅₉).

The spelling of 64696251 in words is "sixty-four million, six hundred ninety-six thousand, two hundred fifty-one".