84470021 has 4 divisors (see below), whose sum is σ = 84499200. Its totient is φ = 84440844.

The previous prime is 84470003. The next prime is 84470033. The reversal of 84470021 is 12007448.

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 a de Polignac number, because none of the positive numbers 2^k-84470021 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 (84470041) 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, 9701 + ... + 16218.

It is an arithmetic number, because the mean of its divisors is an integer number (21124800).

Almost surely, 2^84470021 is an apocalyptic number.

It is an amenable number.

84470021 is a deficient number, since it is larger than the sum of its proper divisors (29179).

84470021 is a wasteful number, since it uses less digits than its factorization.

84470021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29178.

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

The square root of 84470021 is about 9190.7573681389. The cubic root of 84470021 is about 438.7672467199.

Adding to 84470021 its reverse (12007448), we get a palindrome (96477469).

The spelling of 84470021 in words is "eighty-four million, four hundred seventy thousand, twenty-one".