21987300881 has 16 divisors (see below), whose sum is σ = 27994444800. Its totient is φ = 16796662848.

The previous prime is 21987300833. The next prime is 21987300883. The reversal of 21987300881 is 18800378912.

It is not a de Polignac number, because 21987300881 - 2¹⁴ = 21987284497 is a prime.

It is a super-2 number, since 2×21987300881² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21987300883) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4163201 + ... + 4168478.

It is an arithmetic number, because the mean of its divisors is an integer number (1749652800).

Almost surely, 2^21987300881 is an apocalyptic number.

It is an amenable number.

21987300881 is a deficient number, since it is larger than the sum of its proper divisors (6007143919).

21987300881 is a wasteful number, since it uses less digits than its factorization.

21987300881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8331728.

The product of its (nonzero) digits is 193536, while the sum is 47.

The spelling of 21987300881 in words is "twenty-one billion, nine hundred eighty-seven million, three hundred thousand, eight hundred eighty-one".