55991155 has 8 divisors (see below), whose sum is σ = 73297584. Its totient is φ = 40720800.

The previous prime is 55991129. The next prime is 55991179. The reversal of 55991155 is 55119955.

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

It is not a de Polignac number, because 55991155 - 2⁵ = 55991123 is a prime.

It is a Duffinian number.

It is a zygodrome in base 10.

It is an unprimeable number.

It is an upside-down number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 508956 + ... + 509065.

It is an arithmetic number, because the mean of its divisors is an integer number (9162198).

Almost surely, 2^55991155 is an apocalyptic number.

55991155 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

55991155 is a deficient number, since it is larger than the sum of its proper divisors (17306429).

55991155 is a wasteful number, since it uses less digits than its factorization.

55991155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018037.

The product of its digits is 50625, while the sum is 40.

The square root of 55991155 is about 7482.7237687890. The cubic root of 55991155 is about 382.5660927840.

The spelling of 55991155 in words is "fifty-five million, nine hundred ninety-one thousand, one hundred fifty-five".