231928621 has 2 divisors, whose sum is σ = 231928622. Its totient is φ = 231928620.

The previous prime is 231928579. The next prime is 231928657. The reversal of 231928621 is 126829132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148571721 + 83356900 = 12189^2 + 9130^2 .

It is a cyclic number.

It is not a de Polignac number, because 231928621 - 2⁷ = 231928493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231923621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115964310 + 115964311.

It is an arithmetic number, because the mean of its divisors is an integer number (115964311).

Almost surely, 2^231928621 is an apocalyptic number.

It is an amenable number.

231928621 is a deficient number, since it is larger than the sum of its proper divisors (1).

231928621 is an equidigital number, since it uses as much as digits as its factorization.

231928621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 34.

The square root of 231928621 is about 15229.2029010057. The cubic root of 231928621 is about 614.4003417472.

It can be divided in two parts, 23192 and 8621, that added together give a palindrome (31813).

The spelling of 231928621 in words is "two hundred thirty-one million, nine hundred twenty-eight thousand, six hundred twenty-one".