15561356601 has 16 divisors (see below), whose sum is σ = 23787356544. Its totient is φ = 8864148864.

The previous prime is 15561356579. The next prime is 15561356639. The reversal of 15561356601 is 10665316551.

It is not a de Polignac number, because 15561356601 - 2¹⁴ = 15561340217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 15561356601.

It is not an unprimeable number, because it can be changed into a prime (15561356641) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1162140 + ... + 1175453.

It is an arithmetic number, because the mean of its divisors is an integer number (1486709784).

Almost surely, 2^15561356601 is an apocalyptic number.

It is an amenable number.

15561356601 is a deficient number, since it is larger than the sum of its proper divisors (8225999943).

15561356601 is a wasteful number, since it uses less digits than its factorization.

15561356601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2337920.

The product of its (nonzero) digits is 81000, while the sum is 39.

The spelling of 15561356601 in words is "fifteen billion, five hundred sixty-one million, three hundred fifty-six thousand, six hundred one".