21252772043 has 4 divisors (see below), whose sum is σ = 21296412720. Its totient is φ = 21209131368.

The previous prime is 21252772001. The next prime is 21252772067. The reversal of 21252772043 is 34027725212.

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 21252772043 - 2¹⁴ = 21252755659 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21252771994 and 21252772012.

It is not an unprimeable number, because it can be changed into a prime (21252772243) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21819608 + ... + 21820581.

It is an arithmetic number, because the mean of its divisors is an integer number (5324103180).

Almost surely, 2^21252772043 is an apocalyptic number.

21252772043 is a deficient number, since it is larger than the sum of its proper divisors (43640677).

21252772043 is an equidigital number, since it uses as much as digits as its factorization.

21252772043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43640676.

The product of its (nonzero) digits is 47040, while the sum is 35.

The spelling of 21252772043 in words is "twenty-one billion, two hundred fifty-two million, seven hundred seventy-two thousand, forty-three".