68987531 has 2 divisors, whose sum is σ = 68987532. Its totient is φ = 68987530.

The previous prime is 68987519. The next prime is 68987539. The reversal of 68987531 is 13578986.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 68987531 - 2¹⁸ = 68725387 is a prime.

It is a super-2 number, since 2×68987531² = 9518558866951922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (68987539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34493765 + 34493766.

It is an arithmetic number, because the mean of its divisors is an integer number (34493766).

Almost surely, 2^68987531 is an apocalyptic number.

68987531 is a deficient number, since it is larger than the sum of its proper divisors (1).

68987531 is an equidigital number, since it uses as much as digits as its factorization.

68987531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 362880, while the sum is 47.

The square root of 68987531 is about 8305.8732834061. The cubic root of 68987531 is about 410.1318849961.

The spelling of 68987531 in words is "sixty-eight million, nine hundred eighty-seven thousand, five hundred thirty-one".