13122921 has 16 divisors (see below), whose sum is σ = 20194304. Its totient is φ = 7424784.

The previous prime is 13122919. The next prime is 13122937. The reversal of 13122921 is 12922131.

13122921 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13122921 - 2¹ = 13122919 is a prime.

It is a super-2 number, since 2×13122921² = 344422111144482, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13122971) 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, 871 + ... + 5196.

It is an arithmetic number, because the mean of its divisors is an integer number (1262144).

Almost surely, 2^13122921 is an apocalyptic number.

It is an amenable number.

13122921 is a deficient number, since it is larger than the sum of its proper divisors (7071383).

13122921 is a wasteful number, since it uses less digits than its factorization.

13122921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6180.

The product of its digits is 216, while the sum is 21.

The square root of 13122921 is about 3622.5572459245. The cubic root of 13122921 is about 235.8722436461.

The spelling of 13122921 in words is "thirteen million, one hundred twenty-two thousand, nine hundred twenty-one".