21275266369 has 16 divisors (see below), whose sum is σ = 26107474176. Its totient is φ = 16921497600.

The previous prime is 21275266343. The next prime is 21275266379. The reversal of 21275266369 is 96366257212.

It is not a de Polignac number, because 21275266369 - 2¹³ = 21275258177 is a prime.

It is a super-2 number, since 2×21275266369² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21275266379) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1250592 + ... + 1267489.

It is an arithmetic number, because the mean of its divisors is an integer number (1631717136).

Almost surely, 2^21275266369 is an apocalyptic number.

It is an amenable number.

21275266369 is a deficient number, since it is larger than the sum of its proper divisors (4832207807).

21275266369 is a wasteful number, since it uses less digits than its factorization.

21275266369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2518176.

The product of its digits is 1632960, while the sum is 49.

The spelling of 21275266369 in words is "twenty-one billion, two hundred seventy-five million, two hundred sixty-six thousand, three hundred sixty-nine".