22018523721 has 8 divisors (see below), whose sum is σ = 29359592640. Its totient is φ = 14678235312.

The previous prime is 22018523717. The next prime is 22018523741. The reversal of 22018523721 is 12732581022.

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

It is not a de Polignac number, because 22018523721 - 2² = 22018523717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (22018523701) 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, 125781 + ... + 244658.

It is an arithmetic number, because the mean of its divisors is an integer number (3669949080).

Almost surely, 2^22018523721 is an apocalyptic number.

It is an amenable number.

22018523721 is a deficient number, since it is larger than the sum of its proper divisors (7341068919).

22018523721 is a wasteful number, since it uses less digits than its factorization.

22018523721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390255.

The product of its (nonzero) digits is 13440, while the sum is 33.

The spelling of 22018523721 in words is "twenty-two billion, eighteen million, five hundred twenty-three thousand, seven hundred twenty-one".