997661984 has 48 divisors (see below), whose sum is σ = 2235885120. Its totient is φ = 433762560.

The previous prime is 997661957. The next prime is 997661989. The reversal of 997661984 is 489166799.

It is not an unprimeable number, because it can be changed into a prime (997661989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53519 + ... + 69710.

It is an arithmetic number, because the mean of its divisors is an integer number (46580940).

Almost surely, 2^997661984 is an apocalyptic number.

It is an amenable number.

997661984 is an abundant number, since it is smaller than the sum of its proper divisors (1238223136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

997661984 is a wasteful number, since it uses less digits than its factorization.

997661984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123273 (or 123265 counting only the distinct ones).

The product of its digits is 5878656, while the sum is 59.

The square root of 997661984 is about 31585.7876900355. The cubic root of 997661984 is about 999.2200531744.

The spelling of 997661984 in words is "nine hundred ninety-seven million, six hundred sixty-one thousand, nine hundred eighty-four".