21051268253 has 8 divisors (see below), whose sum is σ = 22162552320. Its totient is φ = 19940316480.

The previous prime is 21051268243. The next prime is 21051268261. The reversal of 21051268253 is 35286215012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21051268253 is a prime.

It is a super-3 number, since 3×21051268253³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21051268223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52676 + ... + 211842.

It is an arithmetic number, because the mean of its divisors is an integer number (2770319040).

Almost surely, 2^21051268253 is an apocalyptic number.

It is an amenable number.

21051268253 is a deficient number, since it is larger than the sum of its proper divisors (1111284067).

21051268253 is a wasteful number, since it uses less digits than its factorization.

21051268253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166147.

The product of its (nonzero) digits is 28800, while the sum is 35.

The spelling of 21051268253 in words is "twenty-one billion, fifty-one million, two hundred sixty-eight thousand, two hundred fifty-three".