15565945553 has 8 divisors (see below), whose sum is σ = 15585428928. Its totient is φ = 15546477744.

The previous prime is 15565945541. The next prime is 15565945559. The reversal of 15565945553 is 35554956551.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 15565945553 - 2⁴ = 15565945537 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15565945495 and 15565945504.

It is not an unprimeable number, because it can be changed into a prime (15565945559) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4559075 + ... + 4562487.

It is an arithmetic number, because the mean of its divisors is an integer number (1948178616).

Almost surely, 2^15565945553 is an apocalyptic number.

It is an amenable number.

15565945553 is a deficient number, since it is larger than the sum of its proper divisors (19483375).

15565945553 is a wasteful number, since it uses less digits than its factorization.

15565945553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7783.

The product of its digits is 10125000, while the sum is 53.

The spelling of 15565945553 in words is "fifteen billion, five hundred sixty-five million, nine hundred forty-five thousand, five hundred fifty-three".