21173310947 has 8 divisors (see below), whose sum is σ = 21197682240. Its totient is φ = 21148957440.

The previous prime is 21173310883. The next prime is 21173310973. The reversal of 21173310947 is 74901337112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21173310947 - 2⁶ = 21173310883 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21173310947.

It is not an unprimeable number, because it can be changed into a prime (21173310047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4609622 + ... + 4614212.

It is an arithmetic number, because the mean of its divisors is an integer number (2649710280).

Almost surely, 2^21173310947 is an apocalyptic number.

21173310947 is a deficient number, since it is larger than the sum of its proper divisors (24371293).

21173310947 is a wasteful number, since it uses less digits than its factorization.

21173310947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8893.

The product of its (nonzero) digits is 31752, while the sum is 38.

The spelling of 21173310947 in words is "twenty-one billion, one hundred seventy-three million, three hundred ten thousand, nine hundred forty-seven".