21478794 has 8 divisors (see below), whose sum is σ = 42957600. Its totient is φ = 7159596.

The previous prime is 21478789. The next prime is 21478799. The reversal of 21478794 is 49787412.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21478789) and next prime (21478799).

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

21478794 is an admirable number.

It is a super-2 number, since 2×21478794² = 922677183388872, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21478799) 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, 1789894 + ... + 1789905.

It is an arithmetic number, because the mean of its divisors is an integer number (5369700).

Almost surely, 2^21478794 is an apocalyptic number.

21478794 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21478794 is a wasteful number, since it uses less digits than its factorization.

21478794 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3579804.

The product of its digits is 112896, while the sum is 42.

The square root of 21478794 is about 4634.5219818229. The cubic root of 21478794 is about 277.9734374151.

The spelling of 21478794 in words is "twenty-one million, four hundred seventy-eight thousand, seven hundred ninety-four".