997332551 has 2 divisors, whose sum is σ = 997332552. Its totient is φ = 997332550.

The previous prime is 997332529. The next prime is 997332559. The reversal of 997332551 is 155233799.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-997332551 is a prime.

It is a Sophie Germain prime.

It is a nialpdrome in base 14.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (997332559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 498666275 + 498666276.

It is an arithmetic number, because the mean of its divisors is an integer number (498666276).

Almost surely, 2^997332551 is an apocalyptic number.

997332551 is a deficient number, since it is larger than the sum of its proper divisors (1).

997332551 is an equidigital number, since it uses as much as digits as its factorization.

997332551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 255150, while the sum is 44.

The square root of 997332551 is about 31580.5723665674. The cubic root of 997332551 is about 999.1100585725.

It can be divided in two parts, 9973 and 32551, that added together give a palindrome (42524).

The spelling of 997332551 in words is "nine hundred ninety-seven million, three hundred thirty-two thousand, five hundred fifty-one".