21273524779 has 8 divisors (see below), whose sum is σ = 22913532432. Its totient is φ = 19634028960.

The previous prime is 21273524771. The next prime is 21273524807. The reversal of 21273524779 is 97742537212.

It is a happy number.

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

It is not a de Polignac number, because 21273524779 - 2³ = 21273524771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21273524771) 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, 39352 + ... + 209989.

It is an arithmetic number, because the mean of its divisors is an integer number (2864191554).

Almost surely, 2^21273524779 is an apocalyptic number.

21273524779 is a deficient number, since it is larger than the sum of its proper divisors (1640007653).

21273524779 is a wasteful number, since it uses less digits than its factorization.

21273524779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255917.

The product of its digits is 1481760, while the sum is 49.

The spelling of 21273524779 in words is "twenty-one billion, two hundred seventy-three million, five hundred twenty-four thousand, seven hundred seventy-nine".