21363240881 has 8 divisors (see below), whose sum is σ = 22492509600. Its totient is φ = 20234460960.

The previous prime is 21363240863. The next prime is 21363240887. The reversal of 21363240881 is 18804236312.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21363240881 is a prime.

It is a super-2 number, since 2×21363240881² (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 (21363240887) 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, 30716 + ... + 208973.

It is an arithmetic number, because the mean of its divisors is an integer number (2811563700).

Almost surely, 2^21363240881 is an apocalyptic number.

It is an amenable number.

21363240881 is a deficient number, since it is larger than the sum of its proper divisors (1129268719).

21363240881 is a wasteful number, since it uses less digits than its factorization.

21363240881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244399.

The product of its (nonzero) digits is 55296, while the sum is 38.

The spelling of 21363240881 in words is "twenty-one billion, three hundred sixty-three million, two hundred forty thousand, eight hundred eighty-one".