21315261740 has 48 divisors (see below), whose sum is σ = 45321276000. Its totient is φ = 8420101632.

The previous prime is 21315261731. The next prime is 21315261743. The reversal of 21315261740 is 4716251312.

It is a junction number, because it is equal to n+sod(n) for n = 21315261697 and 21315261706.

It is not an unprimeable number, because it can be changed into a prime (21315261743) 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 15 ways as a sum of consecutive naturals, for example, 653336 + ... + 685184.

It is an arithmetic number, because the mean of its divisors is an integer number (944193250).

Almost surely, 2^21315261740 is an apocalyptic number.

21315261740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21315261740 is an abundant number, since it is smaller than the sum of its proper divisors (24006014260).

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

21315261740 is a wasteful number, since it uses less digits than its factorization.

21315261740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32274 (or 32272 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The spelling of 21315261740 in words is "twenty-one billion, three hundred fifteen million, two hundred sixty-one thousand, seven hundred forty".