12137721 has 8 divisors (see below), whose sum is σ = 16887360. Its totient is φ = 7739952.

The previous prime is 12137701. The next prime is 12137743. The reversal of 12137721 is 12773121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 12137721 - 2¹⁴ = 12121337 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12137691 and 12137700.

It is not an unprimeable number, because it can be changed into a prime (12137701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87886 + ... + 88023.

It is an arithmetic number, because the mean of its divisors is an integer number (2110920).

Almost surely, 2^12137721 is an apocalyptic number.

It is an amenable number.

12137721 is a deficient number, since it is larger than the sum of its proper divisors (4749639).

12137721 is a wasteful number, since it uses less digits than its factorization.

12137721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175935.

The product of its digits is 588, while the sum is 24.

The square root of 12137721 is about 3483.9232195902. The cubic root of 12137721 is about 229.8153590587.

The spelling of 12137721 in words is "twelve million, one hundred thirty-seven thousand, seven hundred twenty-one".