21278474146 has 8 divisors (see below), whose sum is σ = 32321733120. Its totient is φ = 10504563108.

The previous prime is 21278474143. The next prime is 21278474179. The reversal of 21278474146 is 64147487212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21278474096 and 21278474105.

It is not an unprimeable number, because it can be changed into a prime (21278474143) 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, 67336786 + ... + 67337101.

It is an arithmetic number, because the mean of its divisors is an integer number (4040216640).

Almost surely, 2^21278474146 is an apocalyptic number.

21278474146 is a deficient number, since it is larger than the sum of its proper divisors (11043258974).

21278474146 is a wasteful number, since it uses less digits than its factorization.

21278474146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134673968.

The product of its digits is 602112, while the sum is 46.

The spelling of 21278474146 in words is "twenty-one billion, two hundred seventy-eight million, four hundred seventy-four thousand, one hundred forty-six".