653631421 has 2 divisors, whose sum is σ = 653631422. Its totient is φ = 653631420.

The previous prime is 653631403. The next prime is 653631427. The reversal of 653631421 is 124136356.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 625700196 + 27931225 = 25014^2 + 5285^2 .

It is a cyclic number.

It is not a de Polignac number, because 653631421 - 2¹⁵ = 653598653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (653631427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 326815710 + 326815711.

It is an arithmetic number, because the mean of its divisors is an integer number (326815711).

Almost surely, 2^653631421 is an apocalyptic number.

It is an amenable number.

653631421 is a deficient number, since it is larger than the sum of its proper divisors (1).

653631421 is an equidigital number, since it uses as much as digits as its factorization.

653631421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12960, while the sum is 31.

The square root of 653631421 is about 25566.2163997726. The cubic root of 653631421 is about 867.8492791350.

Adding to 653631421 its reverse (124136356), we get a palindrome (777767777).

The spelling of 653631421 in words is "six hundred fifty-three million, six hundred thirty-one thousand, four hundred twenty-one".