84656021 has 4 divisors (see below), whose sum is σ = 86720844. Its totient is φ = 82591200.

The previous prime is 84656003. The next prime is 84656059. The reversal of 84656021 is 12065648.

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 43375396 + 41280625 = 6586^2 + 6425^2 .

It is a cyclic number.

It is not a de Polignac number, because 84656021 - 2⁶ = 84655957 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 (84656521) 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, 1032350 + ... + 1032431.

It is an arithmetic number, because the mean of its divisors is an integer number (21680211).

Almost surely, 2^84656021 is an apocalyptic number.

It is an amenable number.

84656021 is a deficient number, since it is larger than the sum of its proper divisors (2064823).

84656021 is a wasteful number, since it uses less digits than its factorization.

84656021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2064822.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 84656021 is about 9200.8706653229. The cubic root of 84656021 is about 439.0890606163.

The spelling of 84656021 in words is "eighty-four million, six hundred fifty-six thousand, twenty-one".