621522421 has 8 divisors (see below), whose sum is σ = 671516384. Its totient is φ = 571840560.

The previous prime is 621522409. The next prime is 621522437. The reversal of 621522421 is 124225126.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 621522421 - 2²¹ = 619425269 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 (621522401) 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 7 ways as a sum of consecutive naturals, for example, 73875 + ... + 81856.

It is an arithmetic number, because the mean of its divisors is an integer number (83939548).

Almost surely, 2^621522421 is an apocalyptic number.

It is an amenable number.

621522421 is a deficient number, since it is larger than the sum of its proper divisors (49993963).

621522421 is a wasteful number, since it uses less digits than its factorization.

621522421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156051.

The product of its digits is 1920, while the sum is 25.

The square root of 621522421 is about 24930.3514014544. The cubic root of 621522421 is about 853.3992693836.

Adding to 621522421 its reverse (124225126), we get a palindrome (745747547).

The spelling of 621522421 in words is "six hundred twenty-one million, five hundred twenty-two thousand, four hundred twenty-one".