1297198121 has 4 divisors (see below), whose sum is σ = 1299203712. Its totient is φ = 1295192532.

The previous prime is 1297198117. The next prime is 1297198151. The reversal of 1297198121 is 1218917921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1297198121 - 2² = 1297198117 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1297198151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1001825 + ... + 1003118.

It is an arithmetic number, because the mean of its divisors is an integer number (324800928).

Almost surely, 2^1297198121 is an apocalyptic number.

It is an amenable number.

1297198121 is a deficient number, since it is larger than the sum of its proper divisors (2005591).

1297198121 is an equidigital number, since it uses as much as digits as its factorization.

1297198121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2005590.

The product of its digits is 18144, while the sum is 41.

The square root of 1297198121 is about 36016.6367252691. The cubic root of 1297198121 is about 1090.6082291228.

The spelling of 1297198121 in words is "one billion, two hundred ninety-seven million, one hundred ninety-eight thousand, one hundred twenty-one".