21284500506742 has 16 divisors (see below), whose sum is σ = 34829528216400. Its totient is φ = 9674676966240.

The previous prime is 21284500506677. The next prime is 21284500506749. The reversal of 21284500506742 is 24760500548212.

It is a junction number, because it is equal to n+sod(n) for n = 21284500506692 and 21284500506701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21284500506749) 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, 2507517 + ... + 6989752.

It is an arithmetic number, because the mean of its divisors is an integer number (2176845513525).

Almost surely, 2^{21284500506742} is an apocalyptic number.

21284500506742 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21284500506742 is a deficient number, since it is larger than the sum of its proper divisors (13545027709658).

21284500506742 is a wasteful number, since it uses less digits than its factorization.

21284500506742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9599151.

The product of its (nonzero) digits is 1075200, while the sum is 46.

The spelling of 21284500506742 in words is "twenty-one trillion, two hundred eighty-four billion, five hundred million, five hundred six thousand, seven hundred forty-two".