21180015674 has 4 divisors (see below), whose sum is σ = 31770023514. Its totient is φ = 10590007836.

The previous prime is 21180015611. The next prime is 21180015683. The reversal of 21180015674 is 47651008112.

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., 21124587649 + 55428025 = 145343^2 + 7445^2 .

It is a Curzon 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 as a sum of consecutive naturals, namely, 5295003917 + ... + 5295003920.

Almost surely, 2^21180015674 is an apocalyptic number.

21180015674 is a deficient number, since it is larger than the sum of its proper divisors (10590007840).

21180015674 is a wasteful number, since it uses less digits than its factorization.

21180015674 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10590007839.

The product of its (nonzero) digits is 13440, while the sum is 35.

The spelling of 21180015674 in words is "twenty-one billion, one hundred eighty million, fifteen thousand, six hundred seventy-four".