68534640 has 80 divisors (see below), whose sum is σ = 236071200. Its totient is φ = 18275328.

The previous prime is 68534623. The next prime is 68534651. The reversal of 68534640 is 4643586.

68534640 is a `hidden beast` number, since 6 + 8 + 5 + 3 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 68534595 and 68534604.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13705 + ... + 18024.

It is an arithmetic number, because the mean of its divisors is an integer number (2950890).

Almost surely, 2^68534640 is an apocalyptic number.

68534640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

68534640 is an abundant number, since it is smaller than the sum of its proper divisors (167536560).

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

68534640 is a wasteful number, since it uses less digits than its factorization.

68534640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31751 (or 31739 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 68534640 is about 8278.5650930581. The cubic root of 68534640 is about 409.2324326509.

It can be divided in two parts, 6 and 8534640, that added together give a triangular number (8534646 = T₄₁₃₁).

The spelling of 68534640 in words is "sixty-eight million, five hundred thirty-four thousand, six hundred forty".