68400521 has 12 divisors (see below), whose sum is σ = 79844688. Its totient is φ = 58425192.

The previous prime is 68400511. The next prime is 68400523. The reversal of 68400521 is 12500486.

It is not a de Polignac number, because 68400521 - 2¹⁰ = 68399497 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (68400523) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12770 + ... + 17316.

It is an arithmetic number, because the mean of its divisors is an integer number (6653724).

Almost surely, 2^68400521 is an apocalyptic number.

It is an amenable number.

68400521 is a deficient number, since it is larger than the sum of its proper divisors (11444167).

68400521 is a wasteful number, since it uses less digits than its factorization.

68400521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4868 (or 4861 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 68400521 is about 8270.4607489547. The cubic root of 68400521 is about 408.9653089181.

It can be divided in two parts, 68400 and 521, that added together give a cube (68921 = 41³).

The spelling of 68400521 in words is "sixty-eight million, four hundred thousand, five hundred twenty-one".