12811990 has 32 divisors (see below), whose sum is σ = 24470784. Its totient is φ = 4821120.

The previous prime is 12811987. The next prime is 12811991. The reversal of 12811990 is 9911821.

12811990 = 207² + 208² + ... + 361².

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12811991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10912 + ... + 12028.

It is an arithmetic number, because the mean of its divisors is an integer number (764712).

Almost surely, 2^12811990 is an apocalyptic number.

12811990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12811990 is a deficient number, since it is larger than the sum of its proper divisors (11658794).

12811990 is a wasteful number, since it uses less digits than its factorization.

12811990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1192.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 12811990 is about 3579.3840252200. The cubic root of 12811990 is about 233.9944357895.

The spelling of 12811990 in words is "twelve million, eight hundred eleven thousand, nine hundred ninety".