21051763701540 has 384 divisors, whose sum is σ = 74752641331200. Its totient is φ = 4350680463360.

The previous prime is 21051763701481. The next prime is 21051763701571. The reversal of 21051763701540 is 4510736715012.

It is a junction number, because it is equal to n+sod(n) for n = 21051763701492 and 21051763701501.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 3883591 + ... + 7562129.

It is an arithmetic number, because the mean of its divisors is an integer number (194668336800).

Almost surely, 2^{21051763701540} is an apocalyptic number.

21051763701540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21051763701540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37376320665600).

21051763701540 is an abundant number, since it is smaller than the sum of its proper divisors (53700877629660).

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

21051763701540 is a wasteful number, since it uses less digits than its factorization.

21051763701540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3678627 (or 3678625 counting only the distinct ones).

The product of its (nonzero) digits is 176400, while the sum is 42.

The spelling of 21051763701540 in words is "twenty-one trillion, fifty-one billion, seven hundred sixty-three million, seven hundred one thousand, five hundred forty".