21394474 has 4 divisors (see below), whose sum is σ = 32091714. Its totient is φ = 10697236.

The previous prime is 21394459. The next prime is 21394519. The reversal of 21394474 is 47449312.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 13638249 + 7756225 = 3693^2 + 2785^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5348617 + ... + 5348620.

Almost surely, 2^21394474 is an apocalyptic number.

21394474 is a deficient number, since it is larger than the sum of its proper divisors (10697240).

21394474 is a wasteful number, since it uses less digits than its factorization.

21394474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10697239.

The product of its digits is 24192, while the sum is 34.

The square root of 21394474 is about 4625.4160893913. The cubic root of 21394474 is about 277.6092105923.

It can be divided in two parts, 21394 and 474, that multiplied together give a triangular number (10140756 = T₄₅₀₃).

The spelling of 21394474 in words is "twenty-one million, three hundred ninety-four thousand, four hundred seventy-four".