406020621 has 4 divisors (see below), whose sum is σ = 541360832. Its totient is φ = 270680412.

The previous prime is 406020607. The next prime is 406020623. The reversal of 406020621 is 126020604.

It is a happy number.

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 not a de Polignac number, because 406020621 - 2⁷ = 406020493 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 (406020623) 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, 67670101 + ... + 67670106.

It is an arithmetic number, because the mean of its divisors is an integer number (135340208).

Almost surely, 2^406020621 is an apocalyptic number.

It is an amenable number.

406020621 is a deficient number, since it is larger than the sum of its proper divisors (135340211).

406020621 is a wasteful number, since it uses less digits than its factorization.

406020621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135340210.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 406020621 is about 20149.9533746359. The cubic root of 406020621 is about 740.4845991901.

The spelling of 406020621 in words is "four hundred six million, twenty thousand, six hundred twenty-one".