84921221 has 16 divisors (see below), whose sum is σ = 110481408. Its totient is φ = 63294000.

The previous prime is 84921197. The next prime is 84921233. The reversal of 84921221 is 12212948.

It is not a de Polignac number, because 84921221 - 2⁶ = 84921157 is a prime.

It is a super-2 number, since 2×84921221² = 14423227552261682, 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 (84921521) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22205 + ... + 25746.

It is an arithmetic number, because the mean of its divisors is an integer number (6905088).

Almost surely, 2^84921221 is an apocalyptic number.

It is an amenable number.

84921221 is a deficient number, since it is larger than the sum of its proper divisors (25560187).

84921221 is a wasteful number, since it uses less digits than its factorization.

84921221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47992.

The product of its digits is 2304, while the sum is 29.

The square root of 84921221 is about 9215.2710757742. The cubic root of 84921221 is about 439.5470907810.

The spelling of 84921221 in words is "eighty-four million, nine hundred twenty-one thousand, two hundred twenty-one".