15551621157 has 8 divisors (see below), whose sum is σ = 20760693184. Its totient is φ = 10355148288.

The previous prime is 15551621123. The next prime is 15551621177. The reversal of 15551621157 is 75112615551.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 15551621157 - 2²⁴ = 15534843941 is a prime.

It is a super-2 number, since 2×15551621157² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15551621177) 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 in 7 ways as a sum of consecutive naturals, for example, 3146908 + ... + 3151845.

It is an arithmetic number, because the mean of its divisors is an integer number (2595086648).

Almost surely, 2^15551621157 is an apocalyptic number.

It is an amenable number.

15551621157 is a deficient number, since it is larger than the sum of its proper divisors (5209072027).

15551621157 is an equidigital number, since it uses as much as digits as its factorization.

15551621157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6299579.

The product of its digits is 52500, while the sum is 39.

The spelling of 15551621157 in words is "fifteen billion, five hundred fifty-one million, six hundred twenty-one thousand, one hundred fifty-seven".