21239054495 has 4 divisors (see below), whose sum is σ = 25486865400. Its totient is φ = 16991243592.

The previous prime is 21239054387. The next prime is 21239054503. The reversal of 21239054495 is 59445093212.

It is a happy number.

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 21239054495 - 2¹⁰ = 21239053471 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2123905445 + ... + 2123905454.

It is an arithmetic number, because the mean of its divisors is an integer number (6371716350).

Almost surely, 2^21239054495 is an apocalyptic number.

21239054495 is a deficient number, since it is larger than the sum of its proper divisors (4247810905).

21239054495 is an equidigital number, since it uses as much as digits as its factorization.

21239054495 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4247810904.

The product of its (nonzero) digits is 388800, while the sum is 44.

The spelling of 21239054495 in words is "twenty-one billion, two hundred thirty-nine million, fifty-four thousand, four hundred ninety-five".