21957158783 has 8 divisors (see below), whose sum is σ = 25097281152. Its totient is φ = 18817882776.

The previous prime is 21957158779. The next prime is 21957158813. The reversal of 21957158783 is 38785175912.

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

It is not a de Polignac number, because 21957158783 - 2² = 21957158779 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21957158383) 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, 154985 + ... + 260642.

It is an arithmetic number, because the mean of its divisors is an integer number (3137160144).

Almost surely, 2^21957158783 is an apocalyptic number.

21957158783 is a deficient number, since it is larger than the sum of its proper divisors (3140122369).

21957158783 is an equidigital number, since it uses as much as digits as its factorization.

21957158783 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 423181.

The product of its digits is 4233600, while the sum is 56.

The spelling of 21957158783 in words is "twenty-one billion, nine hundred fifty-seven million, one hundred fifty-eight thousand, seven hundred eighty-three".