84970021 has 4 divisors (see below), whose sum is σ = 86946112. Its totient is φ = 82993932.

The previous prime is 84970007. The next prime is 84970043. The reversal of 84970021 is 12007948.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 84970021 - 2⁹ = 84969509 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 (84970421) 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, 987981 + ... + 988066.

It is an arithmetic number, because the mean of its divisors is an integer number (21736528).

Almost surely, 2^84970021 is an apocalyptic number.

It is an amenable number.

84970021 is a deficient number, since it is larger than the sum of its proper divisors (1976091).

84970021 is a wasteful number, since it uses less digits than its factorization.

84970021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1976090.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 84970021 is about 9217.9184743629. The cubic root of 84970021 is about 439.6312699388.

Adding to 84970021 its reverse (12007948), we get a palindrome (96977969).

The spelling of 84970021 in words is "eighty-four million, nine hundred seventy thousand, twenty-one".