653911421 has 2 divisors, whose sum is σ = 653911422. Its totient is φ = 653911420.

The previous prime is 653911393. The next prime is 653911441. The reversal of 653911421 is 124119356.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 544708921 + 109202500 = 23339^2 + 10450^2 .

It is a cyclic number.

It is not a de Polignac number, because 653911421 - 2¹⁸ = 653649277 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (653911441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 326955710 + 326955711.

It is an arithmetic number, because the mean of its divisors is an integer number (326955711).

Almost surely, 2^653911421 is an apocalyptic number.

It is an amenable number.

653911421 is a deficient number, since it is larger than the sum of its proper divisors (1).

653911421 is an equidigital number, since it uses as much as digits as its factorization.

653911421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 32.

The square root of 653911421 is about 25571.6917899462. The cubic root of 653911421 is about 867.9731833724.

The spelling of 653911421 in words is "six hundred fifty-three million, nine hundred eleven thousand, four hundred twenty-one".