1297667921 has 8 divisors (see below), whose sum is σ = 1418796000. Its totient is φ = 1177066240.

The previous prime is 1297667911. The next prime is 1297667941.

1297667921 is nontrivially palindromic in base 10.

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 1297667921 - 2⁶ = 1297667857 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1297667921.

It is not an unprimeable number, because it can be changed into a prime (1297667911) 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, 126431 + ... + 136308.

It is an arithmetic number, because the mean of its divisors is an integer number (177349500).

Almost surely, 2^1297667921 is an apocalyptic number.

1297667921 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1297667921 is a deficient number, since it is larger than the sum of its proper divisors (121128079).

1297667921 is a wasteful number, since it uses less digits than its factorization.

1297667921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263199.

The product of its digits is 571536, while the sum is 50.

The square root of 1297667921 is about 36023.1581208533. The cubic root of 1297667921 is about 1090.7398733428.

The spelling of 1297667921 in words is "one billion, two hundred ninety-seven million, six hundred sixty-seven thousand, nine hundred twenty-one".