55991545 has 16 divisors (see below), whose sum is σ = 72011520. Its totient is φ = 41684544.

The previous prime is 55991519. The next prime is 55991561. The reversal of 55991545 is 54519955.

It is a cyclic number.

It is not a de Polignac number, because 55991545 - 2⁵ = 55991513 is a prime.

It is a super-2 number, since 2×55991545² = 6270106222974050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2325 + ... + 10834.

It is an arithmetic number, because the mean of its divisors is an integer number (4500720).

Almost surely, 2^55991545 is an apocalyptic number.

It is an amenable number.

55991545 is a deficient number, since it is larger than the sum of its proper divisors (16019975).

55991545 is a wasteful number, since it uses less digits than its factorization.

55991545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13224.

The product of its digits is 202500, while the sum is 43.

The square root of 55991545 is about 7482.7498287728. The cubic root of 55991545 is about 382.5669810221.

The spelling of 55991545 in words is "fifty-five million, nine hundred ninety-one thousand, five hundred forty-five".