9721373771 has 2 divisors, whose sum is σ = 9721373772. Its totient is φ = 9721373770.

The previous prime is 9721373743. The next prime is 9721373833. The reversal of 9721373771 is 1773731279.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1773731279) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9721373771 - 2²² = 9717179467 is a prime.

It is not a weakly prime, because it can be changed into another prime (9721373071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4860686885 + 4860686886.

It is an arithmetic number, because the mean of its divisors is an integer number (4860686886).

Almost surely, 2^9721373771 is an apocalyptic number.

9721373771 is a deficient number, since it is larger than the sum of its proper divisors (1).

9721373771 is an equidigital number, since it uses as much as digits as its factorization.

9721373771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 388962, while the sum is 47.

The square root of 9721373771 is about 98597.0271914929. The cubic root of 9721373771 is about 2134.2365202802.

The spelling of 9721373771 in words is "nine billion, seven hundred twenty-one million, three hundred seventy-three thousand, seven hundred seventy-one".