21801333782 has 16 divisors (see below), whose sum is σ = 32973918720. Its totient is φ = 10810317672.

The previous prime is 21801333767. The next prime is 21801333787. The reversal of 21801333782 is 28733310812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21801333787) 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, 78719 + ... + 223157.

It is an arithmetic number, because the mean of its divisors is an integer number (2060869920).

Almost surely, 2^21801333782 is an apocalyptic number.

21801333782 is a deficient number, since it is larger than the sum of its proper divisors (11172584938).

21801333782 is a wasteful number, since it uses less digits than its factorization.

21801333782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145067.

The product of its (nonzero) digits is 48384, while the sum is 38.

The spelling of 21801333782 in words is "twenty-one billion, eight hundred one million, three hundred thirty-three thousand, seven hundred eighty-two".