13747831221 has 16 divisors (see below), whose sum is σ = 18557136000. Its totient is φ = 9052547328.

The previous prime is 13747831217. The next prime is 13747831231. The reversal of 13747831221 is 12213874731.

It is not a de Polignac number, because 13747831221 - 2² = 13747831217 is a prime.

It is a super-2 number, since 2×13747831221² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 13747831221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13747831231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2256 + ... + 165833.

It is an arithmetic number, because the mean of its divisors is an integer number (1159821000).

Almost surely, 2^13747831221 is an apocalyptic number.

It is an amenable number.

13747831221 is a deficient number, since it is larger than the sum of its proper divisors (4809304779).

13747831221 is a wasteful number, since it uses less digits than its factorization.

13747831221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 168428.

The product of its digits is 56448, while the sum is 39.

The spelling of 13747831221 in words is "thirteen billion, seven hundred forty-seven million, eight hundred thirty-one thousand, two hundred twenty-one".