12109400121 has 64 divisors (see below), whose sum is σ = 20168644608. Its totient is φ = 6292435968.

The previous prime is 12109400113. The next prime is 12109400137. The reversal of 12109400121 is 12100490121.

It is a happy number.

It is not a de Polignac number, because 12109400121 - 2³ = 12109400113 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (12109400161) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 12393985 + ... + 12394961.

It is an arithmetic number, because the mean of its divisors is an integer number (315135072).

Almost surely, 2^12109400121 is an apocalyptic number.

It is an amenable number.

12109400121 is a deficient number, since it is larger than the sum of its proper divisors (8059244487).

12109400121 is a wasteful number, since it uses less digits than its factorization.

12109400121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1630.

The product of its (nonzero) digits is 144, while the sum is 21.

Adding to 12109400121 its reverse (12100490121), we get a palindrome (24209890242).

The spelling of 12109400121 in words is "twelve billion, one hundred nine million, four hundred thousand, one hundred twenty-one".