645982982 has 4 divisors (see below), whose sum is σ = 968974476. Its totient is φ = 322991490.

The previous prime is 645982973. The next prime is 645983011. The reversal of 645982982 is 289289546.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×645982982² = 834588026067224648, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 161495744 + ... + 161495747.

It is an arithmetic number, because the mean of its divisors is an integer number (242243619).

Almost surely, 2^645982982 is an apocalyptic number.

645982982 is a deficient number, since it is larger than the sum of its proper divisors (322991494).

645982982 is a wasteful number, since it uses less digits than its factorization.

645982982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 322991493.

The product of its digits is 2488320, while the sum is 53.

The square root of 645982982 is about 25416.1952699455. The cubic root of 645982982 is about 864.4509561094.

The spelling of 645982982 in words is "six hundred forty-five million, nine hundred eighty-two thousand, nine hundred eighty-two".