21127005513 has 24 divisors (see below), whose sum is σ = 31453238856. Its totient is φ = 13655174400.

The previous prime is 21127005509. The next prime is 21127005541. The reversal of 21127005513 is 31550072112.

21127005513 is a `hidden beast` number, since 21 + 127 + 0 + 0 + 5 + 513 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 4827887289 + 16299118224 = 69483^2 + 127668^2 .

It is not a de Polignac number, because 21127005513 - 2² = 21127005509 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21127005583) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19318 + ... + 206463.

It is an arithmetic number, because the mean of its divisors is an integer number (1310551619).

Almost surely, 2^21127005513 is an apocalyptic number.

It is an amenable number.

21127005513 is a deficient number, since it is larger than the sum of its proper divisors (10326233343).

21127005513 is a wasteful number, since it uses less digits than its factorization.

21127005513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226105 (or 226102 counting only the distinct ones).

The product of its (nonzero) digits is 2100, while the sum is 27.

Adding to 21127005513 its reverse (31550072112), we get a palindrome (52677077625).

The spelling of 21127005513 in words is "twenty-one billion, one hundred twenty-seven million, five thousand, five hundred thirteen".