1999872131 has 2 divisors, whose sum is σ = 1999872132. Its totient is φ = 1999872130.

The previous prime is 1999872109. The next prime is 1999872143. The reversal of 1999872131 is 1312789991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1999872131 - 2²⁶ = 1932763267 is a prime.

It is a super-2 number, since 2×1999872131² = 7998977080700962322, 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 1999872131.

It is not a weakly prime, because it can be changed into another prime (1999872431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999936065 + 999936066.

It is an arithmetic number, because the mean of its divisors is an integer number (999936066).

Almost surely, 2^1999872131 is an apocalyptic number.

1999872131 is a deficient number, since it is larger than the sum of its proper divisors (1).

1999872131 is an equidigital number, since it uses as much as digits as its factorization.

1999872131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 244944, while the sum is 50.

The square root of 1999872131 is about 44719.9299082635. The cubic root of 1999872131 is about 1259.8941985152.

It can be divided in two parts, 19998 and 72131, that added together give a palindrome (92129).

The spelling of 1999872131 in words is "one billion, nine hundred ninety-nine million, eight hundred seventy-two thousand, one hundred thirty-one".