21996367081 has 8 divisors (see below), whose sum is σ = 24012894920. Its totient is φ = 20026196352.

The previous prime is 21996367073. The next prime is 21996367111. The reversal of 21996367081 is 18076369912.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 714225625 + 21282141456 = 26725^2 + 145884^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21996367081 - 2³ = 21996367073 is a prime.

It is a super-2 number, since 2×21996367081² (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 (21996367021) 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, 11588286 + ... + 11590183.

It is an arithmetic number, because the mean of its divisors is an integer number (3001611865).

Almost surely, 2^21996367081 is an apocalyptic number.

It is an amenable number.

21996367081 is a deficient number, since it is larger than the sum of its proper divisors (2016527839).

21996367081 is a wasteful number, since it uses less digits than its factorization.

21996367081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23178555.

The product of its (nonzero) digits is 979776, while the sum is 52.

The spelling of 21996367081 in words is "twenty-one billion, nine hundred ninety-six million, three hundred sixty-seven thousand, eighty-one".