2155019775 has 24 divisors (see below), whose sum is σ = 3564295680. Its totient is φ = 1148915040.

The previous prime is 2155019771. The next prime is 2155019791. The reversal of 2155019775 is 5779105512.

It is not a de Polignac number, because 2155019775 - 2² = 2155019771 is a prime.

It is a super-2 number, since 2×2155019775² = 9288220461282101250, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2155019771) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 393204 + ... + 398646.

It is an arithmetic number, because the mean of its divisors is an integer number (148512320).

Almost surely, 2^2155019775 is an apocalyptic number.

2155019775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2155019775 is a deficient number, since it is larger than the sum of its proper divisors (1409275905).

2155019775 is a wasteful number, since it uses less digits than its factorization.

2155019775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10735 (or 10730 counting only the distinct ones).

The product of its (nonzero) digits is 110250, while the sum is 42.

The square root of 2155019775 is about 46422.1905450400. The cubic root of 2155019775 is about 1291.6665708406. Note that the first 3 decimals are identical.

The spelling of 2155019775 in words is "two billion, one hundred fifty-five million, nineteen thousand, seven hundred seventy-five".