21380789876 has 6 divisors (see below), whose sum is σ = 37416382290. Its totient is φ = 10690394936.

The previous prime is 21380789867. The next prime is 21380789879. The reversal of 21380789876 is 67898708312.

It can be written as a sum of positive squares in only one way, i.e., 17421360100 + 3959429776 = 131990^2 + 62924^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21380789879) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2672598731 + ... + 2672598738.

It is an arithmetic number, because the mean of its divisors is an integer number (6236063715).

Almost surely, 2^21380789876 is an apocalyptic number.

It is an amenable number.

21380789876 is a deficient number, since it is larger than the sum of its proper divisors (16035592414).

21380789876 is a wasteful number, since it uses less digits than its factorization.

21380789876 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5345197473 (or 5345197471 counting only the distinct ones).

The product of its (nonzero) digits is 8128512, while the sum is 59.

The spelling of 21380789876 in words is "twenty-one billion, three hundred eighty million, seven hundred eighty-nine thousand, eight hundred seventy-six".