21387877011 has 32 divisors (see below), whose sum is σ = 32376960000. Its totient is φ = 13947858720.

The previous prime is 21387877001. The next prime is 21387877013. The reversal of 21387877011 is 11077878312.

It is a happy number.

It is not a de Polignac number, because 21387877011 - 2¹⁰ = 21387875987 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21387877013) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3485416 + ... + 3491546.

It is an arithmetic number, because the mean of its divisors is an integer number (1011780000).

Almost surely, 2^21387877011 is an apocalyptic number.

21387877011 is a deficient number, since it is larger than the sum of its proper divisors (10989082989).

21387877011 is a wasteful number, since it uses less digits than its factorization.

21387877011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8936 (or 8930 counting only the distinct ones).

The product of its (nonzero) digits is 131712, while the sum is 45.

The spelling of 21387877011 in words is "twenty-one billion, three hundred eighty-seven million, eight hundred seventy-seven thousand, eleven".