40640653 has 2 divisors, whose sum is σ = 40640654. Its totient is φ = 40640652.

The previous prime is 40640647. The next prime is 40640657. The reversal of 40640653 is 35604604.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 39904489 + 736164 = 6317^2 + 858^2 .

It is a cyclic number.

It is not a de Polignac number, because 40640653 - 2²¹ = 38543501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40640657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20320326 + 20320327.

It is an arithmetic number, because the mean of its divisors is an integer number (20320327).

Almost surely, 2^40640653 is an apocalyptic number.

It is an amenable number.

40640653 is a deficient number, since it is larger than the sum of its proper divisors (1).

40640653 is an equidigital number, since it uses as much as digits as its factorization.

40640653 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 40640653 is about 6375.0021960781. The cubic root of 40640653 is about 343.8113627975.

Subtracting from 40640653 its sum of digits (28), we obtain a square (40640625 = 6375²).

The spelling of 40640653 in words is "forty million, six hundred forty thousand, six hundred fifty-three".