21718940277 has 16 divisors (see below), whose sum is σ = 29125573632. Its totient is φ = 14395974000.

The previous prime is 21718940233. The next prime is 21718940281. The reversal of 21718940277 is 77204981712.

It is not a de Polignac number, because 21718940277 - 2⁶ = 21718940213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21718940377) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 490198 + ... + 532664.

It is an arithmetic number, because the mean of its divisors is an integer number (1820348352).

Almost surely, 2^21718940277 is an apocalyptic number.

It is an amenable number.

21718940277 is a deficient number, since it is larger than the sum of its proper divisors (7406633355).

21718940277 is a wasteful number, since it uses less digits than its factorization.

21718940277 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43448.

The product of its (nonzero) digits is 395136, while the sum is 48.

The spelling of 21718940277 in words is "twenty-one billion, seven hundred eighteen million, nine hundred forty thousand, two hundred seventy-seven".