653341981 has 2 divisors, whose sum is σ = 653341982. Its totient is φ = 653341980.

The previous prime is 653341921. The next prime is 653342017. The reversal of 653341981 is 189143356.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 517153081 + 136188900 = 22741^2 + 11670^2 .

It is a cyclic number.

It is not a de Polignac number, because 653341981 - 2¹³ = 653333789 is a prime.

It is a super-2 number, since 2×653341981² = 853711488274008722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (653341921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 326670990 + 326670991.

It is an arithmetic number, because the mean of its divisors is an integer number (326670991).

Almost surely, 2^653341981 is an apocalyptic number.

It is an amenable number.

653341981 is a deficient number, since it is larger than the sum of its proper divisors (1).

653341981 is an equidigital number, since it uses as much as digits as its factorization.

653341981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 77760, while the sum is 40.

The square root of 653341981 is about 25560.5551778517. Note that the first 3 decimals coincide. The cubic root of 653341981 is about 867.7211603544.

The spelling of 653341981 in words is "six hundred fifty-three million, three hundred forty-one thousand, nine hundred eighty-one".