20125531981699 has 2 divisors, whose sum is σ = 20125531981700. Its totient is φ = 20125531981698.

The previous prime is 20125531981691. The next prime is 20125531981721. The reversal of 20125531981699 is 99618913552102.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20125531981699 - 2³ = 20125531981691 is a prime.

It is not a weakly prime, because it can be changed into another prime (20125531981691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10062765990849 + 10062765990850.

It is an arithmetic number, because the mean of its divisors is an integer number (10062765990850).

Almost surely, 2^{20125531981699} is an apocalyptic number.

20125531981699 is a deficient number, since it is larger than the sum of its proper divisors (1).

20125531981699 is an equidigital number, since it uses as much as digits as its factorization.

20125531981699 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10497600, while the sum is 61.

The spelling of 20125531981699 in words is "twenty trillion, one hundred twenty-five billion, five hundred thirty-one million, nine hundred eighty-one thousand, six hundred ninety-nine".