21275266370 has 16 divisors (see below), whose sum is σ = 38646816120. Its totient is φ = 8432031744.

The previous prime is 21275266343. The next prime is 21275266379. The reversal of 21275266370 is 7366257212.

It can be written as a sum of positive squares in 4 ways, for example, as 20644804489 + 630461881 = 143683^2 + 25109^2 .

It is a super-2 number, since 2×21275266370² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

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 7 ways as a sum of consecutive naturals, for example, 9758207 + ... + 9760386.

Almost surely, 2^21275266370 is an apocalyptic number.

21275266370 is a deficient number, since it is larger than the sum of its proper divisors (17371549750).

21275266370 is a wasteful number, since it uses less digits than its factorization.

21275266370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19518709.

The product of its (nonzero) digits is 211680, while the sum is 41.

The spelling of 21275266370 in words is "twenty-one billion, two hundred seventy-five million, two hundred sixty-six thousand, three hundred seventy".