20408911253 has 4 divisors (see below), whose sum is σ = 20413050060. Its totient is φ = 20404772448.

The previous prime is 20408911231. The next prime is 20408911283. The reversal of 20408911253 is 35211980402.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9710525764 + 10698385489 = 98542^2 + 103433^2 .

It is a cyclic number.

It is not a de Polignac number, because 20408911253 - 2⁶ = 20408911189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20408911283) 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, 2061998 + ... + 2071871.

It is an arithmetic number, because the mean of its divisors is an integer number (5103262515).

Almost surely, 2^20408911253 is an apocalyptic number.

It is an amenable number.

20408911253 is a deficient number, since it is larger than the sum of its proper divisors (4138807).

20408911253 is an equidigital number, since it uses as much as digits as its factorization.

20408911253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4138806.

The product of its (nonzero) digits is 17280, while the sum is 35.

The spelling of 20408911253 in words is "twenty billion, four hundred eight million, nine hundred eleven thousand, two hundred fifty-three".