21013276689649 has 4 divisors (see below), whose sum is σ = 21060076860900. Its totient is φ = 20966476518400.

The previous prime is 21013276689637. The next prime is 21013276689661. The reversal of 21013276689649 is 94698667231012.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21013276689637) and next prime (21013276689661).

It can be written as a sum of positive squares in 2 ways, for example, as 14114538052624 + 6898738637025 = 3756932^2 + 2626545^2 .

It is a cyclic number.

It is not a de Polignac number, because 21013276689649 - 2⁵ = 21013276689617 is a prime.

It is a super-3 number, since 3×21013276689649³ (a number of 41 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21013276689049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23400084952 + ... + 23400085849.

It is an arithmetic number, because the mean of its divisors is an integer number (5265019215225).

Almost surely, 2^{21013276689649} is an apocalyptic number.

It is an amenable number.

21013276689649 is a deficient number, since it is larger than the sum of its proper divisors (46800171251).

21013276689649 is an equidigital number, since it uses as much as digits as its factorization.

21013276689649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46800171250.

The product of its (nonzero) digits is 47029248, while the sum is 64.

The spelling of 21013276689649 in words is "twenty-one trillion, thirteen billion, two hundred seventy-six million, six hundred eighty-nine thousand, six hundred forty-nine".