21250253435531 has 4 divisors (see below), whose sum is σ = 21253078147752. Its totient is φ = 21247428723312.

The previous prime is 21250253435519. The next prime is 21250253435561. The reversal of 21250253435531 is 13553435205212.

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

It is a cyclic number.

It is not a de Polignac number, because 21250253435531 - 2¹⁰ = 21250253434507 is a prime.

It is a super-2 number, since 2×21250253435531² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21250253435501) 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, 1412344826 + ... + 1412359871.

It is an arithmetic number, because the mean of its divisors is an integer number (5313269536938).

Almost surely, 2^{21250253435531} is an apocalyptic number.

21250253435531 is a deficient number, since it is larger than the sum of its proper divisors (2824712221).

21250253435531 is an equidigital number, since it uses as much as digits as its factorization.

21250253435531 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2824712220.

The product of its (nonzero) digits is 540000, while the sum is 41.

The spelling of 21250253435531 in words is "twenty-one trillion, two hundred fifty billion, two hundred fifty-three million, four hundred thirty-five thousand, five hundred thirty-one".