21751032340 has 12 divisors (see below), whose sum is σ = 45677167956. Its totient is φ = 8700412928.

The previous prime is 21751032307. The next prime is 21751032341. The reversal of 21751032340 is 4323015712.

It can be written as a sum of positive squares in 2 ways, for example, as 4259911824 + 17491120516 = 65268^2 + 132254^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21751032299 and 21751032308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21751032341) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 543775789 + ... + 543775828.

It is an arithmetic number, because the mean of its divisors is an integer number (3806430663).

Almost surely, 2^21751032340 is an apocalyptic number.

21751032340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21751032340 is an abundant number, since it is smaller than the sum of its proper divisors (23926135616).

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

21751032340 is a wasteful number, since it uses less digits than its factorization.

21751032340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1087551626 (or 1087551624 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The spelling of 21751032340 in words is "twenty-one billion, seven hundred fifty-one million, thirty-two thousand, three hundred forty".