68306531 has 4 divisors (see below), whose sum is σ = 68390352. Its totient is φ = 68222712.

The previous prime is 68306471. The next prime is 68306543. The reversal of 68306531 is 13560386.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 68306531 - 2⁶ = 68306467 is a prime.

It is a super-2 number, since 2×68306531² = 9331564354507922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (68306131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 40676 + ... + 42321.

It is an arithmetic number, because the mean of its divisors is an integer number (17097588).

Almost surely, 2^68306531 is an apocalyptic number.

68306531 is a deficient number, since it is larger than the sum of its proper divisors (83821).

68306531 is an equidigital number, since it uses as much as digits as its factorization.

68306531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83820.

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 68306531 is about 8264.7765245045. The cubic root of 68306531 is about 408.7779016264. Note that the first 3 decimals are identical.

The spelling of 68306531 in words is "sixty-eight million, three hundred six thousand, five hundred thirty-one".