78354631 has 4 divisors (see below), whose sum is σ = 78391264. Its totient is φ = 78318000.

The previous prime is 78354611. The next prime is 78354667. The reversal of 78354631 is 13645387.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13645387 = 7 ⋅1949341.

It is a cyclic number.

It is not a de Polignac number, because 78354631 - 2⁵ = 78354599 is a prime.

It is a super-2 number, since 2×78354631² = 12278896398292322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78354611) 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, 14895 + ... + 19456.

It is an arithmetic number, because the mean of its divisors is an integer number (19597816).

Almost surely, 2^78354631 is an apocalyptic number.

78354631 is a deficient number, since it is larger than the sum of its proper divisors (36633).

78354631 is a wasteful number, since it uses less digits than its factorization.

78354631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36632.

The product of its digits is 60480, while the sum is 37.

The square root of 78354631 is about 8851.8151245945. The cubic root of 78354631 is about 427.9124180271.

The spelling of 78354631 in words is "seventy-eight million, three hundred fifty-four thousand, six hundred thirty-one".