221440031 has 4 divisors (see below), whose sum is σ = 223509672. Its totient is φ = 219370392.

The previous prime is 221440019. The next prime is 221440061. The reversal of 221440031 is 130044122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221440031 is a prime.

It is a super-2 number, since 2×221440031² = 98071374658561922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221439991 and 221440009.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221440061) 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, 1034660 + ... + 1034873.

It is an arithmetic number, because the mean of its divisors is an integer number (55877418).

Almost surely, 2^221440031 is an apocalyptic number.

221440031 is a deficient number, since it is larger than the sum of its proper divisors (2069641).

221440031 is a wasteful number, since it uses less digits than its factorization.

221440031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2069640.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 221440031 is about 14880.8612317970. The cubic root of 221440031 is about 604.9953609370.

Adding to 221440031 its reverse (130044122), we get a palindrome (351484153).

The spelling of 221440031 in words is "two hundred twenty-one million, four hundred forty thousand, thirty-one".