421570091 has 4 divisors (see below), whose sum is σ = 421611384. Its totient is φ = 421528800.

The previous prime is 421570073. The next prime is 421570169. The reversal of 421570091 is 190075124.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 421570091 - 2¹⁴ = 421553707 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (421570001) 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, 7076 + ... + 29886.

It is an arithmetic number, because the mean of its divisors is an integer number (105402846).

Almost surely, 2^421570091 is an apocalyptic number.

421570091 is a deficient number, since it is larger than the sum of its proper divisors (41293).

421570091 is a wasteful number, since it uses less digits than its factorization.

421570091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41292.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 421570091 is about 20532.1720964929. The cubic root of 421570091 is about 749.8192696374.

The spelling of 421570091 in words is "four hundred twenty-one million, five hundred seventy thousand, ninety-one".