8742320621 has 2 divisors, whose sum is σ = 8742320622. Its totient is φ = 8742320620.

The previous prime is 8742320519. The next prime is 8742320623. The reversal of 8742320621 is 1260232478.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6510230596 + 2232090025 = 80686^2 + 47245^2 .

It is a cyclic number.

It is not a de Polignac number, because 8742320621 - 2¹⁴ = 8742304237 is a prime.

Together with 8742320623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (8742320623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4371160310 + 4371160311.

It is an arithmetic number, because the mean of its divisors is an integer number (4371160311).

Almost surely, 2^8742320621 is an apocalyptic number.

It is an amenable number.

8742320621 is a deficient number, since it is larger than the sum of its proper divisors (1).

8742320621 is an equidigital number, since it uses as much as digits as its factorization.

8742320621 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32256, while the sum is 35.

The square root of 8742320621 is about 93500.3776516437. The cubic root of 8742320621 is about 2060.0396370448.

The spelling of 8742320621 in words is "eight billion, seven hundred forty-two million, three hundred twenty thousand, six hundred twenty-one".