21731007867 has 16 divisors (see below), whose sum is σ = 30685712640. Its totient is φ = 13650623712.

The previous prime is 21731007839. The next prime is 21731007917. The reversal of 21731007867 is 76870013712.

It is a happy number.

It is not a de Polignac number, because 21731007867 - 2¹⁴ = 21730991483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21731007167) 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, 2345692 + ... + 2354937.

It is an arithmetic number, because the mean of its divisors is an integer number (1917857040).

Almost surely, 2^21731007867 is an apocalyptic number.

21731007867 is a deficient number, since it is larger than the sum of its proper divisors (8954704773).

21731007867 is a wasteful number, since it uses less digits than its factorization.

21731007867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4700722.

The product of its (nonzero) digits is 98784, while the sum is 42.

The spelling of 21731007867 in words is "twenty-one billion, seven hundred thirty-one million, seven thousand, eight hundred sixty-seven".