21783043957 has 8 divisors (see below), whose sum is σ = 21931892640. Its totient is φ = 21634497360.

The previous prime is 21783043951. The next prime is 21783044011. The reversal of 21783043957 is 75934038712.

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 21783043957 - 2³ = 21783043949 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21783043957.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21783043951) 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, 70143 + ... + 220195.

It is an arithmetic number, because the mean of its divisors is an integer number (2741486580).

Almost surely, 2^21783043957 is an apocalyptic number.

It is an amenable number.

21783043957 is a deficient number, since it is larger than the sum of its proper divisors (148848683).

21783043957 is a wasteful number, since it uses less digits than its factorization.

21783043957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151043.

The product of its (nonzero) digits is 1270080, while the sum is 49.

The spelling of 21783043957 in words is "twenty-one billion, seven hundred eighty-three million, forty-three thousand, nine hundred fifty-seven".