2155693221 has 96 divisors (see below), whose sum is σ = 3703864320. Its totient is φ = 1195084800.

The previous prime is 2155693217. The next prime is 2155693261. The reversal of 2155693221 is 1223965512.

It is a happy number.

It is not a de Polignac number, because 2155693221 - 2² = 2155693217 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2155693201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4716825 + ... + 4717281.

It is an arithmetic number, because the mean of its divisors is an integer number (38581920).

Almost surely, 2^2155693221 is an apocalyptic number.

It is an amenable number.

2155693221 is a deficient number, since it is larger than the sum of its proper divisors (1548171099).

2155693221 is a wasteful number, since it uses less digits than its factorization.

2155693221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 587 (or 584 counting only the distinct ones).

The product of its digits is 32400, while the sum is 36.

The square root of 2155693221 is about 46429.4434707116. The cubic root of 2155693221 is about 1291.8011058921.

The spelling of 2155693221 in words is "two billion, one hundred fifty-five million, six hundred ninety-three thousand, two hundred twenty-one".