136400640 has 72 divisors (see below), whose sum is σ = 435641808. Its totient is φ = 36372480.

The previous prime is 136400609. The next prime is 136400653. The reversal of 136400640 is 46004631.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 136400640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13921 + ... + 21600.

Almost surely, 2^136400640 is an apocalyptic number.

136400640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

136400640 is an abundant number, since it is smaller than the sum of its proper divisors (299241168).

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

136400640 is an equidigital number, since it uses as much as digits as its factorization.

136400640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35545 (or 35531 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 136400640 is about 11679.0684560028. The cubic root of 136400640 is about 514.7608026090.

The spelling of 136400640 in words is "one hundred thirty-six million, four hundred thousand, six hundred forty".