420021715 has 4 divisors (see below), whose sum is σ = 504026064. Its totient is φ = 336017368.

The previous prime is 420021709. The next prime is 420021781. The reversal of 420021715 is 517120024.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 420021715 - 2¹⁷ = 419890643 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42002167 + ... + 42002176.

It is an arithmetic number, because the mean of its divisors is an integer number (126006516).

Almost surely, 2^420021715 is an apocalyptic number.

420021715 is a deficient number, since it is larger than the sum of its proper divisors (84004349).

420021715 is an equidigital number, since it uses as much as digits as its factorization.

420021715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84004348.

The product of its (nonzero) digits is 560, while the sum is 22.

The square root of 420021715 is about 20494.4313168236. The cubic root of 420021715 is about 748.9001449172.

Adding to 420021715 its reverse (517120024), we get a palindrome (937141739).

The spelling of 420021715 in words is "four hundred twenty million, twenty-one thousand, seven hundred fifteen".