1311920121 has 8 divisors (see below), whose sum is σ = 1758106944. Its totient is φ = 870173360.

The previous prime is 1311920111. The next prime is 1311920123. The reversal of 1311920121 is 1210291131.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1311920121 - 2⁷ = 1311919993 is a prime.

It is a super-2 number, since 2×1311920121² = 3442268807769309282, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1311920123) 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, 1109325 + ... + 1110506.

It is an arithmetic number, because the mean of its divisors is an integer number (219763368).

Almost surely, 2^1311920121 is an apocalyptic number.

It is an amenable number.

1311920121 is a deficient number, since it is larger than the sum of its proper divisors (446186823).

1311920121 is a wasteful number, since it uses less digits than its factorization.

1311920121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2220031.

The product of its (nonzero) digits is 108, while the sum is 21.

The square root of 1311920121 is about 36220.4378907820. The cubic root of 1311920121 is about 1094.7185173352.

The spelling of 1311920121 in words is "one billion, three hundred eleven million, nine hundred twenty thousand, one hundred twenty-one".