99906521831 has 2 divisors, whose sum is σ = 99906521832. Its totient is φ = 99906521830.

The previous prime is 99906521807. The next prime is 99906521863. The reversal of 99906521831 is 13812560999.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (13812560999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99906521831 - 2²² = 99902327527 is a prime.

It is a super-2 number, since 2×99906521831² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99906521801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49953260915 + 49953260916.

It is an arithmetic number, because the mean of its divisors is an integer number (49953260916).

Almost surely, 2^99906521831 is an apocalyptic number.

99906521831 is a deficient number, since it is larger than the sum of its proper divisors (1).

99906521831 is an equidigital number, since it uses as much as digits as its factorization.

99906521831 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1049760, while the sum is 53.

The spelling of 99906521831 in words is "ninety-nine billion, nine hundred six million, five hundred twenty-one thousand, eight hundred thirty-one".