21452401565 has 16 divisors (see below), whose sum is σ = 30434935680. Its totient is φ = 14202968640.

The previous prime is 21452401519. The next prime is 21452401577. The reversal of 21452401565 is 56510425412.

It is not a de Polignac number, because 21452401565 - 2¹⁸ = 21452139421 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10566671 + ... + 10568700.

It is an arithmetic number, because the mean of its divisors is an integer number (1902183480).

Almost surely, 2^21452401565 is an apocalyptic number.

It is an amenable number.

21452401565 is a deficient number, since it is larger than the sum of its proper divisors (8982534115).

21452401565 is a wasteful number, since it uses less digits than its factorization.

21452401565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21135412.

The product of its (nonzero) digits is 48000, while the sum is 35.

Adding to 21452401565 its reverse (56510425412), we get a palindrome (77962826977).

The spelling of 21452401565 in words is "twenty-one billion, four hundred fifty-two million, four hundred one thousand, five hundred sixty-five".