64140840 has 48 divisors (see below), whose sum is σ = 208458900. Its totient is φ = 17104128.

The previous prime is 64140809. The next prime is 64140871. The reversal of 64140840 is 4804146.

64140840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (64140809) and next prime (64140871).

It can be written as a sum of positive squares in 2 ways, for example, as 61496964 + 2643876 = 7842^2 + 1626^2 .

It is a super-2 number, since 2×64140840² = 8228094711811200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 88725 + ... + 89444.

Almost surely, 2^64140840 is an apocalyptic number.

64140840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64140840 is an abundant number, since it is smaller than the sum of its proper divisors (144318060).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64140840 is a wasteful number, since it uses less digits than its factorization.

64140840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 178186 (or 178179 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 64140840 is about 8008.7976625708. The cubic root of 64140840 is about 400.2932016961.

Adding to 64140840 its reverse (4804146), we get a palindrome (68944986).

It can be divided in two parts, 64140 and 840, that added together give a triangular number (64980 = T₃₆₀).

The spelling of 64140840 in words is "sixty-four million, one hundred forty thousand, eight hundred forty".