405420421 has 4 divisors (see below), whose sum is σ = 463337632. Its totient is φ = 347503212.

The previous prime is 405420413. The next prime is 405420439. The reversal of 405420421 is 124024504.

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 405420421 - 2³ = 405420413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 405420392 and 405420401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (405420481) 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, 28958595 + ... + 28958608.

It is an arithmetic number, because the mean of its divisors is an integer number (115834408).

Almost surely, 2^405420421 is an apocalyptic number.

It is an amenable number.

405420421 is a deficient number, since it is larger than the sum of its proper divisors (57917211).

405420421 is an equidigital number, since it uses as much as digits as its factorization.

405420421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57917210.

The product of its (nonzero) digits is 1280, while the sum is 22.

The square root of 405420421 is about 20135.0545318358. The cubic root of 405420421 is about 740.1195454541.

Adding to 405420421 its reverse (124024504), we get a palindrome (529444925).

The spelling of 405420421 in words is "four hundred five million, four hundred twenty thousand, four hundred twenty-one".