21266462540 has 12 divisors (see below), whose sum is σ = 44659571376. Its totient is φ = 8506585008.

The previous prime is 21266462533. The next prime is 21266462543. The reversal of 21266462540 is 4526466212.

It is a junction number, because it is equal to n+sod(n) for n = 21266462494 and 21266462503.

It is not an unprimeable number, because it can be changed into a prime (21266462543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 531661544 + ... + 531661583.

It is an arithmetic number, because the mean of its divisors is an integer number (3721630948).

Almost surely, 2^21266462540 is an apocalyptic number.

21266462540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21266462540 is an abundant number, since it is smaller than the sum of its proper divisors (23393108836).

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

21266462540 is a wasteful number, since it uses less digits than its factorization.

21266462540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1063323136 (or 1063323134 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 38.

The spelling of 21266462540 in words is "twenty-one billion, two hundred sixty-six million, four hundred sixty-two thousand, five hundred forty".