64845631 has 2 divisors, whose sum is σ = 64845632. Its totient is φ = 64845630.

The previous prime is 64845619. The next prime is 64845637. The reversal of 64845631 is 13654846.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64845631 - 2⁷ = 64845503 is a prime.

It is a super-2 number, since 2×64845631² = 8409911719576322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64845637) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32422815 + 32422816.

It is an arithmetic number, because the mean of its divisors is an integer number (32422816).

Almost surely, 2^64845631 is an apocalyptic number.

64845631 is a deficient number, since it is larger than the sum of its proper divisors (1).

64845631 is an equidigital number, since it uses as much as digits as its factorization.

64845631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 69120, while the sum is 37.

The square root of 64845631 is about 8052.6784984873. The cubic root of 64845631 is about 401.7540284677.

The spelling of 64845631 in words is "sixty-four million, eight hundred forty-five thousand, six hundred thirty-one".