21179254 has 4 divisors (see below), whose sum is σ = 31768884. Its totient is φ = 10589626.

The previous prime is 21179239. The next prime is 21179287. The reversal of 21179254 is 45297112.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5294812 + ... + 5294815.

It is an arithmetic number, because the mean of its divisors is an integer number (7942221).

Almost surely, 2^21179254 is an apocalyptic number.

21179254 is a deficient number, since it is larger than the sum of its proper divisors (10589630).

21179254 is a wasteful number, since it uses less digits than its factorization.

21179254 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10589629.

The product of its digits is 5040, while the sum is 31.

The square root of 21179254 is about 4602.0923502251. The cubic root of 21179254 is about 276.6751917503.

The spelling of 21179254 in words is "twenty-one million, one hundred seventy-nine thousand, two hundred fifty-four".