82247021 has 4 divisors (see below), whose sum is σ = 82280892. Its totient is φ = 82213152.

The previous prime is 82247017. The next prime is 82247023. The reversal of 82247021 is 12074228.

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 43744996 + 38502025 = 6614^2 + 6205^2 .

It is a cyclic number.

It is not a de Polignac number, because 82247021 - 2² = 82247017 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (82247023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12986 + ... + 18251.

It is an arithmetic number, because the mean of its divisors is an integer number (20570223).

Almost surely, 2^82247021 is an apocalyptic number.

It is an amenable number.

82247021 is a deficient number, since it is larger than the sum of its proper divisors (33871).

82247021 is a wasteful number, since it uses less digits than its factorization.

82247021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33870.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 82247021 is about 9069.0143345349. The cubic root of 82247021 is about 434.8839625316.

The spelling of 82247021 in words is "eighty-two million, two hundred forty-seven thousand, twenty-one".