21179249474 has 4 divisors (see below), whose sum is σ = 31768874214. Its totient is φ = 10589624736.

The previous prime is 21179249473. The next prime is 21179249491. The reversal of 21179249474 is 47494297112.

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., 11652123025 + 9527126449 = 107945^2 + 97607^2 .

It is not an unprimeable number, because it can be changed into a prime (21179249473) 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, 5294812367 + ... + 5294812370.

Almost surely, 2^21179249474 is an apocalyptic number.

21179249474 is a deficient number, since it is larger than the sum of its proper divisors (10589624740).

21179249474 is a wasteful number, since it uses less digits than its factorization.

21179249474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10589624739.

The product of its digits is 1016064, while the sum is 50.

The spelling of 21179249474 in words is "twenty-one billion, one hundred seventy-nine million, two hundred forty-nine thousand, four hundred seventy-four".