21678150012 has 24 divisors (see below), whose sum is σ = 50612204496. Its totient is φ = 7221785088.

The previous prime is 21678150001. The next prime is 21678150017. The reversal of 21678150012 is 21005187612.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21678150017) 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, 511903 + ... + 552630.

It is an arithmetic number, because the mean of its divisors is an integer number (2108841854).

Almost surely, 2^21678150012 is an apocalyptic number.

It is an amenable number.

21678150012 is an abundant number, since it is smaller than the sum of its proper divisors (28934054484).

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

21678150012 is a wasteful number, since it uses less digits than its factorization.

21678150012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1066237 (or 1066235 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 33.

The spelling of 21678150012 in words is "twenty-one billion, six hundred seventy-eight million, one hundred fifty thousand, twelve".