396857820 has 48 divisors (see below), whose sum is σ = 1115347968. Its totient is φ = 105433920.

The previous prime is 396857789. The next prime is 396857821. The reversal of 396857820 is 28758693.

It is a super-2 number, since 2×396857820² = 314992258590304800, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 396857820.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (396857821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4057 + ... + 28463.

It is an arithmetic number, because the mean of its divisors is an integer number (23236416).

Almost surely, 2^396857820 is an apocalyptic number.

396857820 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

396857820 is an abundant number, since it is smaller than the sum of its proper divisors (718490148).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

396857820 is a wasteful number, since it uses less digits than its factorization.

396857820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24690 (or 24688 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 48.

The square root of 396857820 is about 19921.2906208408. The cubic root of 396857820 is about 734.8719106699.

The spelling of 396857820 in words is "three hundred ninety-six million, eight hundred fifty-seven thousand, eight hundred twenty".