561021982 has 4 divisors (see below), whose sum is σ = 841532976. Its totient is φ = 280510990.

The previous prime is 561021961. The next prime is 561022027. The reversal of 561021982 is 289120165.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140255494 + ... + 140255497.

It is an arithmetic number, because the mean of its divisors is an integer number (210383244).

Almost surely, 2^561021982 is an apocalyptic number.

561021982 is a deficient number, since it is larger than the sum of its proper divisors (280510994).

561021982 is a wasteful number, since it uses less digits than its factorization.

561021982 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 280510993.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 561021982 is about 23685.9026004921. The cubic root of 561021982 is about 824.7581694625.

The spelling of 561021982 in words is "five hundred sixty-one million, twenty-one thousand, nine hundred eighty-two".