21275771725 has 48 divisors (see below), whose sum is σ = 28702162944. Its totient is φ = 15551424000.

The previous prime is 21275771707. The next prime is 21275771743. The reversal of 21275771725 is 52717757212.

It is an interprime number because it is at equal distance from previous prime (21275771707) and next prime (21275771743).

It is not a de Polignac number, because 21275771725 - 2¹¹ = 21275769677 is a prime.

It is a Smith number, since the sum of its digits (46) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 14462740 + ... + 14464210.

It is an arithmetic number, because the mean of its divisors is an integer number (597961728).

Almost surely, 2^21275771725 is an apocalyptic number.

21275771725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21275771725 is a deficient number, since it is larger than the sum of its proper divisors (7426391219).

21275771725 is a wasteful number, since it uses less digits than its factorization.

21275771725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1918 (or 1913 counting only the distinct ones).

The product of its digits is 480200, while the sum is 46.

It can be divided in two parts, 212757 and 71725, that added together give a palindrome (284482).

The spelling of 21275771725 in words is "twenty-one billion, two hundred seventy-five million, seven hundred seventy-one thousand, seven hundred twenty-five".