997720065 has 16 divisors (see below), whose sum is σ = 1773724800. Its totient is φ = 532117296.

The previous prime is 997720051. The next prime is 997720081. The reversal of 997720065 is 560027799.

It is not a de Polignac number, because 997720065 - 2⁴ = 997720049 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 997720065.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3695125 + ... + 3695394.

It is an arithmetic number, because the mean of its divisors is an integer number (110857800).

It is a Proth number, since it is equal to 1903 ⋅ 2¹⁹ + 1 and 1903 < 2¹⁹.

Almost surely, 2^997720065 is an apocalyptic number.

It is an amenable number.

997720065 is a deficient number, since it is larger than the sum of its proper divisors (776004735).

997720065 is a wasteful number, since it uses less digits than its factorization.

997720065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7390533 (or 7390527 counting only the distinct ones).

The product of its (nonzero) digits is 238140, while the sum is 45.

The square root of 997720065 is about 31586.7070933328. The cubic root of 997720065 is about 999.2394433669.

The spelling of 997720065 in words is "nine hundred ninety-seven million, seven hundred twenty thousand, sixty-five".