78589631 has 2 divisors, whose sum is σ = 78589632. Its totient is φ = 78589630.

The previous prime is 78589613. The next prime is 78589663. The reversal of 78589631 is 13698587.

It is a happy number.

Together with previous prime (78589613) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78589631 is a prime.

It is a super-2 number, since 2×78589631² = 12352660201432322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78589531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39294815 + 39294816.

It is an arithmetic number, because the mean of its divisors is an integer number (39294816).

Almost surely, 2^78589631 is an apocalyptic number.

78589631 is a deficient number, since it is larger than the sum of its proper divisors (1).

78589631 is an equidigital number, since it uses as much as digits as its factorization.

78589631 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 78589631 is about 8865.0793002657. The cubic root of 78589631 is about 428.3397871651.

The spelling of 78589631 in words is "seventy-eight million, five hundred eighty-nine thousand, six hundred thirty-one".