921100055 has 16 divisors (see below), whose sum is σ = 1168812288. Its totient is φ = 695712000.

The previous prime is 921100051. The next prime is 921100087. The reversal of 921100055 is 550001129.

It is not a de Polignac number, because 921100055 - 2² = 921100051 is a prime.

It is a super-2 number, since 2×921100055² = 1696850622642006050, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 921100055.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (921100051) 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, 66116 + ... + 78825.

It is an arithmetic number, because the mean of its divisors is an integer number (73050768).

Almost surely, 2^921100055 is an apocalyptic number.

921100055 is a deficient number, since it is larger than the sum of its proper divisors (247712233).

921100055 is a wasteful number, since it uses less digits than its factorization.

921100055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145018.

The product of its (nonzero) digits is 450, while the sum is 23.

The square root of 921100055 is about 30349.6302283899. The cubic root of 921100055 is about 972.9763171801.

The spelling of 921100055 in words is "nine hundred twenty-one million, one hundred thousand, fifty-five".