64444442531 has 32 divisors (see below), whose sum is σ = 75307799040. Its totient is φ = 54007430400.

The previous prime is 64444442521. The next prime is 64444442539. The reversal of 64444442531 is 13524444446.

It is not a de Polignac number, because 64444442531 - 2⁶ = 64444442467 is a prime.

It is a super-2 number, since 2×64444442531² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64444442539) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 87204560 + ... + 87205298.

It is an arithmetic number, because the mean of its divisors is an integer number (2353368720).

Almost surely, 2^64444442531 is an apocalyptic number.

64444442531 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

64444442531 is a deficient number, since it is larger than the sum of its proper divisors (10863356509).

64444442531 is a wasteful number, since it uses less digits than its factorization.

64444442531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1755.

The product of its digits is 737280, while the sum is 41.

Adding to 64444442531 its reverse (13524444446), we get a palindrome (77968886977).

The spelling of 64444442531 in words is "sixty-four billion, four hundred forty-four million, four hundred forty-two thousand, five hundred thirty-one".