21684041718702 has 32 divisors (see below), whose sum is σ = 50093615096064. Its totient is φ = 6184396924800.

The previous prime is 21684041718679. The next prime is 21684041718709. The reversal of 21684041718702 is 20781714048612.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21684041718709) 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, 9663119074 + ... + 9663121317.

It is an arithmetic number, because the mean of its divisors is an integer number (1565425471752).

Almost surely, 2^{21684041718702} is an apocalyptic number.

21684041718702 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21684041718702 is an abundant number, since it is smaller than the sum of its proper divisors (28409573377362).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21684041718702 is a wasteful number, since it uses less digits than its factorization.

21684041718702 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19326240424.

The product of its (nonzero) digits is 1204224, while the sum is 51.

The spelling of 21684041718702 in words is "twenty-one trillion, six hundred eighty-four billion, forty-one million, seven hundred eighteen thousand, seven hundred two".