21242253255 has 32 divisors (see below), whose sum is σ = 34273704960. Its totient is φ = 11233971840.

The previous prime is 21242253229. The next prime is 21242253257. The reversal of 21242253255 is 55235224212.

It is not a de Polignac number, because 21242253255 - 2⁵ = 21242253223 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21242253257) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3107181 + ... + 3114009.

It is an arithmetic number, because the mean of its divisors is an integer number (1071053280).

Almost surely, 2^21242253255 is an apocalyptic number.

21242253255 is a deficient number, since it is larger than the sum of its proper divisors (13031451705).

21242253255 is a wasteful number, since it uses less digits than its factorization.

21242253255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8551.

The product of its digits is 48000, while the sum is 33.

Adding to 21242253255 its reverse (55235224212), we get a palindrome (76477477467).

The spelling of 21242253255 in words is "twenty-one billion, two hundred forty-two million, two hundred fifty-three thousand, two hundred fifty-five".