21671961796 has 9 divisors (see below), whose sum is σ = 37926448399. Its totient is φ = 10835833684.

The previous prime is 21671961763. The next prime is 21671961803. The reversal of 21671961796 is 69716917612.

The square root of 21671961796 is 147214.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 257625 + ... + 331231.

Almost surely, 2^21671961796 is an apocalyptic number.

21671961796 is the 147214-th square number.

It is an amenable number.

21671961796 is a deficient number, since it is larger than the sum of its proper divisors (16254486603).

21671961796 is an frugal number, since it uses more digits than its factorization.

21671961796 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147218 (or 73609 counting only the distinct ones).

The product of its digits is 1714608, while the sum is 55.

The spelling of 21671961796 in words is "twenty-one billion, six hundred seventy-one million, nine hundred sixty-one thousand, seven hundred ninety-six".