4221531 has 8 divisors (see below), whose sum is σ = 6254160. Its totient is φ = 2814336.

The previous prime is 4221521. The next prime is 4221533. The reversal of 4221531 is 1351224.

It is not a de Polignac number, because 4221531 - 2⁵ = 4221499 is a prime.

It is a super-2 number, since 2×4221531² = 35642647967922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (4221533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78150 + ... + 78203.

It is an arithmetic number, because the mean of its divisors is an integer number (781770).

Almost surely, 2^4221531 is an apocalyptic number.

4221531 is a deficient number, since it is larger than the sum of its proper divisors (2032629).

4221531 is a wasteful number, since it uses less digits than its factorization.

4221531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156362 (or 156356 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 4221531 is about 2054.6364641951. The cubic root of 4221531 is about 161.6180990373.

Adding to 4221531 its reverse (1351224), we get a palindrome (5572755).

It can be divided in two parts, 422 and 1531, that added together give a triangular number (1953 = T₆₂).

The spelling of 4221531 in words is "four million, two hundred twenty-one thousand, five hundred thirty-one".