331632421 has 4 divisors (see below), whose sum is σ = 331668844. Its totient is φ = 331596000.

The previous prime is 331632407. The next prime is 331632437. The reversal of 331632421 is 124236133.

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 can be written as a sum of positive squares in 2 ways, for example, as 43956900 + 287675521 = 6630^2 + 16961^2 .

It is a cyclic number.

It is not a de Polignac number, because 331632421 - 2²³ = 323243813 is a prime.

It is a super-3 number, since 3×331632421³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331632461) 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, 8971 + ... + 27271.

It is an arithmetic number, because the mean of its divisors is an integer number (82917211).

Almost surely, 2^331632421 is an apocalyptic number.

It is an amenable number.

331632421 is a deficient number, since it is larger than the sum of its proper divisors (36423).

331632421 is a wasteful number, since it uses less digits than its factorization.

331632421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36422.

The product of its digits is 2592, while the sum is 25.

The square root of 331632421 is about 18210.7776055829. Note that the first 3 decimals coincide. The cubic root of 331632421 is about 692.1799159362.

Adding to 331632421 its reverse (124236133), we get a palindrome (455868554).

The spelling of 331632421 in words is "three hundred thirty-one million, six hundred thirty-two thousand, four hundred twenty-one".