1551165516 has 18 divisors (see below), whose sum is σ = 3921001812. Its totient is φ = 517055160.

The previous prime is 1551165463. The next prime is 1551165521. The reversal of 1551165516 is 6155611551.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×1551165516² = 4812228916055092512, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 43087931 = 1551165516 / (1 + 5 + 5 + 1 + 1 + 6 + 5 + 5 + 1 + 6).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 21543930 + ... + 21544001.

It is an arithmetic number, because the mean of its divisors is an integer number (217833434).

Almost surely, 2^1551165516 is an apocalyptic number.

It is an amenable number.

1551165516 is an abundant number, since it is smaller than the sum of its proper divisors (2369836296).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1551165516 is a wasteful number, since it uses less digits than its factorization.

1551165516 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43087941 (or 43087936 counting only the distinct ones).

The product of its digits is 22500, while the sum is 36.

The square root of 1551165516 is about 39384.8386565186. The cubic root of 1551165516 is about 1157.5845288421.

The spelling of 1551165516 in words is "one billion, five hundred fifty-one million, one hundred sixty-five thousand, five hundred sixteen".