55151999 has 16 divisors (see below), whose sum is σ = 67123200. Its totient is φ = 45211320.

The previous prime is 55151989. The next prime is 55152001. The reversal of 55151999 is 99915155.

It is a happy number.

It is not a de Polignac number, because 55151999 - 2⁴ = 55151983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55151989) 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, 4394 + ... + 11384.

It is an arithmetic number, because the mean of its divisors is an integer number (4195200).

Almost surely, 2^55151999 is an apocalyptic number.

55151999 is a deficient number, since it is larger than the sum of its proper divisors (11971201).

55151999 is an equidigital number, since it uses as much as digits as its factorization.

55151999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7035 (or 7021 counting only the distinct ones).

The product of its digits is 91125, while the sum is 44.

The square root of 55151999 is about 7426.4391871206. The cubic root of 55151999 is about 380.6452541298.

The spelling of 55151999 in words is "fifty-five million, one hundred fifty-one thousand, nine hundred ninety-nine".