21540505740654 has 32 divisors (see below), whose sum is σ = 43182990474624. Its totient is φ = 7163192141280.

The previous prime is 21540505740631. The next prime is 21540505740659. The reversal of 21540505740654 is 45604750504512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21540505740659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1790032 + ... + 6803324.

It is an arithmetic number, because the mean of its divisors is an integer number (1349468452332).

Almost surely, 2^{21540505740654} is an apocalyptic number.

21540505740654 is an abundant number, since it is smaller than the sum of its proper divisors (21642484733970).

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

21540505740654 is a wasteful number, since it uses less digits than its factorization.

21540505740654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5014992.

The product of its (nonzero) digits is 3360000, while the sum is 48.

The spelling of 21540505740654 in words is "twenty-one trillion, five hundred forty billion, five hundred five million, seven hundred forty thousand, six hundred fifty-four".