1297547621 has 2 divisors, whose sum is σ = 1297547622. Its totient is φ = 1297547620.

The previous prime is 1297547617. The next prime is 1297547683. The reversal of 1297547621 is 1267457921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1109556100 + 187991521 = 33310^2 + 13711^2 .

It is a cyclic number.

It is not a de Polignac number, because 1297547621 - 2² = 1297547617 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1297547611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 648773810 + 648773811.

It is an arithmetic number, because the mean of its divisors is an integer number (648773811).

Almost surely, 2^1297547621 is an apocalyptic number.

It is an amenable number.

1297547621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1297547621 is an equidigital number, since it uses as much as digits as its factorization.

1297547621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 211680, while the sum is 44.

The square root of 1297547621 is about 36021.4883229441. The cubic root of 1297547621 is about 1090.7061667066.

The spelling of 1297547621 in words is "one billion, two hundred ninety-seven million, five hundred forty-seven thousand, six hundred twenty-one".