421520023 has 4 divisors (see below), whose sum is σ = 421564248. Its totient is φ = 421475800.

The previous prime is 421519991. The next prime is 421520059. The reversal of 421520023 is 320025124.

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 421520023 - 2⁵ = 421519991 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 (421524023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1261 + ... + 29062.

It is an arithmetic number, because the mean of its divisors is an integer number (105391062).

Almost surely, 2^421520023 is an apocalyptic number.

421520023 is a deficient number, since it is larger than the sum of its proper divisors (44225).

421520023 is a wasteful number, since it uses less digits than its factorization.

421520023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44224.

The product of its (nonzero) digits is 480, while the sum is 19.

The square root of 421520023 is about 20530.9528030240. The cubic root of 421520023 is about 749.7895842317.

Adding to 421520023 its reverse (320025124), we get a palindrome (741545147).

The spelling of 421520023 in words is "four hundred twenty-one million, five hundred twenty thousand, twenty-three".