79882021 has 4 divisors (see below), whose sum is σ = 79922700. Its totient is φ = 79841344.

The previous prime is 79881973. The next prime is 79882051. The reversal of 79882021 is 12028897.

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

It can be written as a sum of positive squares in 2 ways, for example, as 17313921 + 62568100 = 4161^2 + 7910^2 .

It is a cyclic number.

It is not a de Polignac number, because 79882021 - 2⁹ = 79881509 is a prime.

It is a super-2 number, since 2×79882021² = 12762274558088882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79882051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17236 + ... + 21373.

It is an arithmetic number, because the mean of its divisors is an integer number (19980675).

Almost surely, 2^79882021 is an apocalyptic number.

It is an amenable number.

79882021 is a deficient number, since it is larger than the sum of its proper divisors (40679).

79882021 is a wasteful number, since it uses less digits than its factorization.

79882021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40678.

The product of its (nonzero) digits is 16128, while the sum is 37.

The square root of 79882021 is about 8937.6742500496. The cubic root of 79882021 is about 430.6750187552.

The spelling of 79882021 in words is "seventy-nine million, eight hundred eighty-two thousand, twenty-one".