21562402547 has 4 divisors (see below), whose sum is σ = 24642745776. Its totient is φ = 18482059320.

The previous prime is 21562402513. The next prime is 21562402553. The reversal of 21562402547 is 74520426512.

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 21562402547 - 2³⁰ = 20488660723 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21562402547.

It is not an unprimeable number, because it can be changed into a prime (21562402577) 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, 1540171604 + ... + 1540171617.

It is an arithmetic number, because the mean of its divisors is an integer number (6160686444).

Almost surely, 2^21562402547 is an apocalyptic number.

21562402547 is a deficient number, since it is larger than the sum of its proper divisors (3080343229).

21562402547 is an equidigital number, since it uses as much as digits as its factorization.

21562402547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3080343228.

The product of its (nonzero) digits is 134400, while the sum is 38.

The spelling of 21562402547 in words is "twenty-one billion, five hundred sixty-two million, four hundred two thousand, five hundred forty-seven".