15631471081 has 2 divisors, whose sum is σ = 15631471082. Its totient is φ = 15631471080.

The previous prime is 15631471021. The next prime is 15631471111. The reversal of 15631471081 is 18017413651.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15351210000 + 280261081 = 123900^2 + 16741^2 .

It is a cyclic number.

It is not a de Polignac number, because 15631471081 - 2¹¹ = 15631469033 is a prime.

It is a super-2 number, since 2×15631471081² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 15631471081.

It is not a weakly prime, because it can be changed into another prime (15631471001) 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, 7815735540 + 7815735541.

It is an arithmetic number, because the mean of its divisors is an integer number (7815735541).

Almost surely, 2^15631471081 is an apocalyptic number.

It is an amenable number.

15631471081 is a deficient number, since it is larger than the sum of its proper divisors (1).

15631471081 is an equidigital number, since it uses as much as digits as its factorization.

15631471081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 37.

The spelling of 15631471081 in words is "fifteen billion, six hundred thirty-one million, four hundred seventy-one thousand, eighty-one".