2101221431 has 4 divisors (see below), whose sum is σ = 2107569864. Its totient is φ = 2094873000.

The previous prime is 2101221413. The next prime is 2101221461. The reversal of 2101221431 is 1341221012.

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-2101221431 is a prime.

It is a super-2 number, since 2×2101221431² = 8830263004187375522, 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 (2101221461) 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, 3173720 + ... + 3174381.

It is an arithmetic number, because the mean of its divisors is an integer number (526892466).

Almost surely, 2^2101221431 is an apocalyptic number.

2101221431 is a deficient number, since it is larger than the sum of its proper divisors (6348433).

2101221431 is an equidigital number, since it uses as much as digits as its factorization.

2101221431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6348432.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 2101221431 is about 45839.0819170716. The cubic root of 2101221431 is about 1280.8273929138.

Adding to 2101221431 its reverse (1341221012), we get a palindrome (3442442443).

The spelling of 2101221431 in words is "two billion, one hundred one million, two hundred twenty-one thousand, four hundred thirty-one".