21743956957 has 8 divisors (see below), whose sum is σ = 22274748576. Its totient is φ = 21219231792.

The previous prime is 21743956903. The next prime is 21743956961. The reversal of 21743956957 is 75965934712.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21743956957 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 (21743956987) 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, 1509358 + ... + 1523695.

It is an arithmetic number, because the mean of its divisors is an integer number (2784343572).

Almost surely, 2^21743956957 is an apocalyptic number.

It is an amenable number.

21743956957 is a deficient number, since it is larger than the sum of its proper divisors (530791619).

21743956957 is a wasteful number, since it uses less digits than its factorization.

21743956957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3033227.

The product of its digits is 14288400, while the sum is 58.

The spelling of 21743956957 in words is "twenty-one billion, seven hundred forty-three million, nine hundred fifty-six thousand, nine hundred fifty-seven".