15581942149 has 2 divisors, whose sum is σ = 15581942150. Its totient is φ = 15581942148.

The previous prime is 15581942099. The next prime is 15581942153. The reversal of 15581942149 is 94124918551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9011704900 + 6570237249 = 94930^2 + 81057^2 .

It is an emirp because it is prime and its reverse (94124918551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15581942149 - 2²¹ = 15579844997 is a prime.

It is a super-2 number, since 2×15581942149² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15581942249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7790971074 + 7790971075.

It is an arithmetic number, because the mean of its divisors is an integer number (7790971075).

Almost surely, 2^15581942149 is an apocalyptic number.

It is an amenable number.

15581942149 is a deficient number, since it is larger than the sum of its proper divisors (1).

15581942149 is an equidigital number, since it uses as much as digits as its factorization.

15581942149 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 518400, while the sum is 49.

The spelling of 15581942149 in words is "fifteen billion, five hundred eighty-one million, nine hundred forty-two thousand, one hundred forty-nine".