781423631 has 4 divisors (see below), whose sum is σ = 781560264. Its totient is φ = 781287000.

The previous prime is 781423619. The next prime is 781423637. The reversal of 781423631 is 136324187.

781423631 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 781423631 - 2¹⁴ = 781407247 is a prime.

It is a super-2 number, since 2×781423631² = 1221245782170448322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 781423591 and 781423600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (781423637) 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, 59345 + ... + 71306.

It is an arithmetic number, because the mean of its divisors is an integer number (195390066).

Almost surely, 2^781423631 is an apocalyptic number.

781423631 is a deficient number, since it is larger than the sum of its proper divisors (136633).

781423631 is a wasteful number, since it uses less digits than its factorization.

781423631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136632.

The product of its digits is 24192, while the sum is 35.

The square root of 781423631 is about 27953.9555519429. The cubic root of 781423631 is about 921.0761002272.

The spelling of 781423631 in words is "seven hundred eighty-one million, four hundred twenty-three thousand, six hundred thirty-one".