640265453 has 2 divisors, whose sum is σ = 640265454. Its totient is φ = 640265452.

The previous prime is 640265449. The next prime is 640265489. The reversal of 640265453 is 354562046.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 638421289 + 1844164 = 25267^2 + 1358^2 .

It is a cyclic number.

It is not a de Polignac number, because 640265453 - 2² = 640265449 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (640265653) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 320132726 + 320132727.

It is an arithmetic number, because the mean of its divisors is an integer number (320132727).

Almost surely, 2^640265453 is an apocalyptic number.

It is an amenable number.

640265453 is a deficient number, since it is larger than the sum of its proper divisors (1).

640265453 is an equidigital number, since it uses as much as digits as its factorization.

640265453 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 86400, while the sum is 35.

The square root of 640265453 is about 25303.4672130125. The cubic root of 640265453 is about 861.8930056171.

The spelling of 640265453 in words is "six hundred forty million, two hundred sixty-five thousand, four hundred fifty-three".