997646990 has 16 divisors (see below), whose sum is σ = 1798733952. Its totient is φ = 398398944.

The previous prime is 997646987. The next prime is 997647031. The reversal of 997646990 is 99646799.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 76109 + ... + 88248.

It is an arithmetic number, because the mean of its divisors is an integer number (112420872).

Almost surely, 2^997646990 is an apocalyptic number.

997646990 is a deficient number, since it is larger than the sum of its proper divisors (801086962).

997646990 is a wasteful number, since it uses less digits than its factorization.

997646990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164971.

The product of its (nonzero) digits is 6613488, while the sum is 59.

The square root of 997646990 is about 31585.5503355569. The cubic root of 997646990 is about 999.2150473439.

The spelling of 997646990 in words is "nine hundred ninety-seven million, six hundred forty-six thousand, nine hundred ninety".