2155241691 has 48 divisors (see below), whose sum is σ = 3466251360. Its totient is φ = 1284111360.

The previous prime is 2155241681. The next prime is 2155241717. The reversal of 2155241691 is 1961425512.

2155241691 is a `hidden beast` number, since 2 + 1 + 552 + 4 + 16 + 91 = 666.

It is not a de Polignac number, because 2155241691 - 2⁷ = 2155241563 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2155241681) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 266676 + ... + 274638.

It is an arithmetic number, because the mean of its divisors is an integer number (72213570).

Almost surely, 2^2155241691 is an apocalyptic number.

2155241691 is a deficient number, since it is larger than the sum of its proper divisors (1311009669).

2155241691 is a wasteful number, since it uses less digits than its factorization.

2155241691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8076 (or 8073 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 2155241691 is about 46424.5806766200. The cubic root of 2155241691 is about 1291.7109063409.

The spelling of 2155241691 in words is "two billion, one hundred fifty-five million, two hundred forty-one thousand, six hundred ninety-one".