431099021 has 2 divisors, whose sum is σ = 431099022. Its totient is φ = 431099020.

The previous prime is 431099003. The next prime is 431099027. The reversal of 431099021 is 120990134.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 315772900 + 115326121 = 17770^2 + 10739^2 .

It is a cyclic number.

It is not a de Polignac number, because 431099021 - 2²² = 426904717 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (431099027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 215549510 + 215549511.

It is an arithmetic number, because the mean of its divisors is an integer number (215549511).

Almost surely, 2^431099021 is an apocalyptic number.

It is an amenable number.

431099021 is a deficient number, since it is larger than the sum of its proper divisors (1).

431099021 is an equidigital number, since it uses as much as digits as its factorization.

431099021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 431099021 is about 20762.9241919340. The cubic root of 431099021 is about 755.4267260073.

The spelling of 431099021 in words is "four hundred thirty-one million, ninety-nine thousand, twenty-one".