1390812820 has 24 divisors (see below), whose sum is σ = 2924405064. Its totient is φ = 555620736.

The previous prime is 1390812781. The next prime is 1390812877. The reversal of 1390812820 is 282180931.

It can be written as a sum of positive squares in 4 ways, for example, as 22108804 + 1368704016 = 4702^2 + 36996^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27687 + ... + 59566.

It is an arithmetic number, because the mean of its divisors is an integer number (121850211).

Almost surely, 2^1390812820 is an apocalyptic number.

1390812820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1390812820 is an abundant number, since it is smaller than the sum of its proper divisors (1533592244).

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

1390812820 is a wasteful number, since it uses less digits than its factorization.

1390812820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88059 (or 88057 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 1390812820 is about 37293.6029366968. The cubic root of 1390812820 is about 1116.2365229253.

The spelling of 1390812820 in words is "one billion, three hundred ninety million, eight hundred twelve thousand, eight hundred twenty".