21751482678 has 16 divisors (see below), whose sum is σ = 43505313840. Its totient is φ = 7250102816.

The previous prime is 21751482671. The next prime is 21751482679. The reversal of 21751482678 is 87628415712.

It is a happy number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21751482678.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21751482671) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36808 + ... + 211796.

It is an arithmetic number, because the mean of its divisors is an integer number (2719082115).

Almost surely, 2^21751482678 is an apocalyptic number.

21751482678 is an abundant number, since it is smaller than the sum of its proper divisors (21753831162).

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

21751482678 is a wasteful number, since it uses less digits than its factorization.

21751482678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195711.

The product of its digits is 1505280, while the sum is 51.

The spelling of 21751482678 in words is "twenty-one billion, seven hundred fifty-one million, four hundred eighty-two thousand, six hundred seventy-eight".