291292921 has 2 divisors, whose sum is σ = 291292922. Its totient is φ = 291292920.

The previous prime is 291292901. The next prime is 291292927. The reversal of 291292921 is 129292192.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 287777296 + 3515625 = 16964^2 + 1875^2 .

It is a cyclic number.

It is not a de Polignac number, because 291292921 - 2⁵ = 291292889 is a prime.

It is not a weakly prime, because it can be changed into another prime (291292927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 145646460 + 145646461.

It is an arithmetic number, because the mean of its divisors is an integer number (145646461).

Almost surely, 2^291292921 is an apocalyptic number.

It is an amenable number.

291292921 is a deficient number, since it is larger than the sum of its proper divisors (1).

291292921 is an equidigital number, since it uses as much as digits as its factorization.

291292921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11664, while the sum is 37.

The square root of 291292921 is about 17067.3056162946. The cubic root of 291292921 is about 662.8928125424.

The spelling of 291292921 in words is "two hundred ninety-one million, two hundred ninety-two thousand, nine hundred twenty-one".