21494686 has 4 divisors (see below), whose sum is σ = 32242032. Its totient is φ = 10747342.

The previous prime is 21494677. The next prime is 21494689. The reversal of 21494686 is 68649412.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21494689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5373670 + ... + 5373673.

It is an arithmetic number, because the mean of its divisors is an integer number (8060508).

Almost surely, 2^21494686 is an apocalyptic number.

21494686 is a deficient number, since it is larger than the sum of its proper divisors (10747346).

21494686 is a wasteful number, since it uses less digits than its factorization.

21494686 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10747345.

The product of its digits is 82944, while the sum is 40.

The square root of 21494686 is about 4636.2361889792. The cubic root of 21494686 is about 278.0419773404.

The spelling of 21494686 in words is "twenty-one million, four hundred ninety-four thousand, six hundred eighty-six".