21457758229 has 4 divisors (see below), whose sum is σ = 21551460460. Its totient is φ = 21364056000.

The previous prime is 21457758227. The next prime is 21457758233. The reversal of 21457758229 is 92285775412.

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 19827456100 + 1630302129 = 140810^2 + 40377^2 .

It is a cyclic number.

It is not a de Polignac number, because 21457758229 - 2¹ = 21457758227 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 (21457758227) 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, 46850772 + ... + 46851229.

It is an arithmetic number, because the mean of its divisors is an integer number (5387865115).

Almost surely, 2^21457758229 is an apocalyptic number.

It is an amenable number.

21457758229 is a deficient number, since it is larger than the sum of its proper divisors (93702231).

21457758229 is an equidigital number, since it uses as much as digits as its factorization.

21457758229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93702230.

The product of its digits is 2822400, while the sum is 52.

The spelling of 21457758229 in words is "twenty-one billion, four hundred fifty-seven million, seven hundred fifty-eight thousand, two hundred twenty-nine".