999999955 has 4 divisors (see below), whose sum is σ = 1199999952. Its totient is φ = 799999960.

The previous prime is 999999937. The next prime is 1000000007. The reversal of 999999955 is 559999999.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 999999955 - 2²⁷ = 865782227 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 99999991 + ... + 100000000.

It is an arithmetic number, because the mean of its divisors is an integer number (299999988).

Almost surely, 2^999999955 is an apocalyptic number.

999999955 is a deficient number, since it is larger than the sum of its proper divisors (199999997).

999999955 is a wasteful number, since it uses less digits than its factorization.

999999955 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199999996.

The product of its digits is 119574225, while the sum is 73.

The square root of 999999955 is about 31622.7758901713. The cubic root of 999999955 is about 999.9999850000. Note that the first 4 decimals are identical.

It can be divided in two parts, 99999995 and 5, that added together give a 8-th power (100000000 = 10⁸).

The spelling of 999999955 in words is "nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred fifty-five".