9901129531 has 2 divisors, whose sum is σ = 9901129532. Its totient is φ = 9901129530.

The previous prime is 9901129507. The next prime is 9901129549. The reversal of 9901129531 is 1359211099.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 9901129531 - 2⁹ = 9901129019 is a prime.

It is a super-2 number, since 2×9901129531² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9901129571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4950564765 + 4950564766.

It is an arithmetic number, because the mean of its divisors is an integer number (4950564766).

Almost surely, 2^9901129531 is an apocalyptic number.

9901129531 is a deficient number, since it is larger than the sum of its proper divisors (1).

9901129531 is an equidigital number, since it uses as much as digits as its factorization.

9901129531 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21870, while the sum is 40.

The square root of 9901129531 is about 99504.4196556113. The cubic root of 9901129531 is about 2147.3108279306.

The spelling of 9901129531 in words is "nine billion, nine hundred one million, one hundred twenty-nine thousand, five hundred thirty-one".