40640253 has 4 divisors (see below), whose sum is σ = 54187008. Its totient is φ = 27093500.

The previous prime is 40640239. The next prime is 40640311. The reversal of 40640253 is 35204604.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40640253 - 2¹² = 40636157 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40640053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6773373 + ... + 6773378.

It is an arithmetic number, because the mean of its divisors is an integer number (13546752).

Almost surely, 2^40640253 is an apocalyptic number.

It is an amenable number.

40640253 is a deficient number, since it is larger than the sum of its proper divisors (13546755).

40640253 is a wasteful number, since it uses less digits than its factorization.

40640253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13546754.

The product of its (nonzero) digits is 2880, while the sum is 24.

The square root of 40640253 is about 6374.9708234626. The cubic root of 40640253 is about 343.8102348219.

Adding to 40640253 its reverse (35204604), we get a palindrome (75844857).

The spelling of 40640253 in words is "forty million, six hundred forty thousand, two hundred fifty-three".