21035726881 has 16 divisors (see below), whose sum is σ = 22859774784. Its totient is φ = 19241838144.

The previous prime is 21035726851. The next prime is 21035726923. The reversal of 21035726881 is 18862753012.

It is a cyclic number.

It is not a de Polignac number, because 21035726881 - 2³¹ = 18888243233 is a prime.

It is a super-2 number, since 2×21035726881² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21035726821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 675210 + ... + 705676.

It is an arithmetic number, because the mean of its divisors is an integer number (1428735924).

Almost surely, 2^21035726881 is an apocalyptic number.

It is an amenable number.

21035726881 is a deficient number, since it is larger than the sum of its proper divisors (1824047903).

21035726881 is a wasteful number, since it uses less digits than its factorization.

21035726881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30960.

The product of its (nonzero) digits is 161280, while the sum is 43.

The spelling of 21035726881 in words is "twenty-one billion, thirty-five million, seven hundred twenty-six thousand, eight hundred eighty-one".