21858966791 has 8 divisors (see below), whose sum is σ = 22600685184. Its totient is φ = 21119535360.

The previous prime is 21858966769. The next prime is 21858966797. The reversal of 21858966791 is 19766985812.

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 21858966791 - 2¹⁰ = 21858965767 is a prime.

It is a super-3 number, since 3×21858966791³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21858966797) 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, 552290 + ... + 590543.

It is an arithmetic number, because the mean of its divisors is an integer number (2825085648).

Almost surely, 2^21858966791 is an apocalyptic number.

21858966791 is a deficient number, since it is larger than the sum of its proper divisors (741718393).

21858966791 is a wasteful number, since it uses less digits than its factorization.

21858966791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1143481.

The product of its digits is 13063680, while the sum is 62.

The spelling of 21858966791 in words is "twenty-one billion, eight hundred fifty-eight million, nine hundred sixty-six thousand, seven hundred ninety-one".