685220631 has 8 divisors (see below), whose sum is σ = 929112960. Its totient is φ = 449071032.

The previous prime is 685220629. The next prime is 685220633. The reversal of 685220631 is 136022586.

It is an interprime number because it is at equal distance from previous prime (685220629) and next prime (685220633).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 685220631 - 2¹ = 685220629 is a prime.

It is a super-2 number, since 2×685220631² = 939054626296076322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 685220592 and 685220601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685220633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1935475 + ... + 1935828.

It is an arithmetic number, because the mean of its divisors is an integer number (116139120).

Almost surely, 2^685220631 is an apocalyptic number.

685220631 is a deficient number, since it is larger than the sum of its proper divisors (243892329).

685220631 is a wasteful number, since it uses less digits than its factorization.

685220631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3871365.

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 685220631 is about 26176.7192558579. The cubic root of 685220631 is about 881.6106140054.

The spelling of 685220631 in words is "six hundred eighty-five million, two hundred twenty thousand, six hundred thirty-one".