997447657 has 2 divisors, whose sum is σ = 997447658. Its totient is φ = 997447656.

The previous prime is 997447639. The next prime is 997447673. The reversal of 997447657 is 756744799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 875035561 + 122412096 = 29581^2 + 11064^2 .

It is a cyclic number.

It is not a de Polignac number, because 997447657 - 2¹⁵ = 997414889 is a prime.

It is not a weakly prime, because it can be changed into another prime (997447697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498723828 + 498723829.

It is an arithmetic number, because the mean of its divisors is an integer number (498723829).

Almost surely, 2^997447657 is an apocalyptic number.

It is an amenable number.

997447657 is a deficient number, since it is larger than the sum of its proper divisors (1).

997447657 is an equidigital number, since it uses as much as digits as its factorization.

997447657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13335840, while the sum is 58.

The square root of 997447657 is about 31582.3947318755. The cubic root of 997447657 is about 999.1484941436.

The spelling of 997447657 in words is "nine hundred ninety-seven million, four hundred forty-seven thousand, six hundred fifty-seven".