220521431 has 4 divisors (see below), whose sum is σ = 237484632. Its totient is φ = 203558232.

The previous prime is 220521419. The next prime is 220521437. The reversal of 220521431 is 134125022.

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 220521431 - 2²² = 216327127 is a prime.

It is a super-2 number, since 2×220521431² = 97259403060575522, which contains 22 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 (220521437) 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, 8481581 + ... + 8481606.

It is an arithmetic number, because the mean of its divisors is an integer number (59371158).

Almost surely, 2^220521431 is an apocalyptic number.

220521431 is a deficient number, since it is larger than the sum of its proper divisors (16963201).

220521431 is a wasteful number, since it uses less digits than its factorization.

220521431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16963200.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 220521431 is about 14849.9640066904. The cubic root of 220521431 is about 604.1576337759.

Adding to 220521431 its reverse (134125022), we get a palindrome (354646453).

The spelling of 220521431 in words is "two hundred twenty million, five hundred twenty-one thousand, four hundred thirty-one".