21369240775 has 24 divisors (see below), whose sum is σ = 27662229504. Its totient is φ = 16344847200.

The previous prime is 21369240769. The next prime is 21369240793. The reversal of 21369240775 is 57704296312.

It is not a de Polignac number, because 21369240775 - 2⁵ = 21369240743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1538110 + ... + 1551940.

It is an arithmetic number, because the mean of its divisors is an integer number (1152592896).

Almost surely, 2^21369240775 is an apocalyptic number.

21369240775 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21369240775 is a deficient number, since it is larger than the sum of its proper divisors (6292988729).

21369240775 is a wasteful number, since it uses less digits than its factorization.

21369240775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16551 (or 16546 counting only the distinct ones).

The product of its (nonzero) digits is 635040, while the sum is 46.

It can be divided in two parts, 21369 and 240775, that added together give a 18-th power (262144 = 2¹⁸).

The spelling of 21369240775 in words is "twenty-one billion, three hundred sixty-nine million, two hundred forty thousand, seven hundred seventy-five".