7389170021 has 2 divisors, whose sum is σ = 7389170022. Its totient is φ = 7389170020.

The previous prime is 7389169933. The next prime is 7389170023. The reversal of 7389170021 is 1200719837.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7209877921 + 179292100 = 84911^2 + 13390^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7389170021 is a prime.

Together with 7389170023, 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 (7389170023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3694585010 + 3694585011.

It is an arithmetic number, because the mean of its divisors is an integer number (3694585011).

Almost surely, 2^7389170021 is an apocalyptic number.

It is an amenable number.

7389170021 is a deficient number, since it is larger than the sum of its proper divisors (1).

7389170021 is an equidigital number, since it uses as much as digits as its factorization.

7389170021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21168, while the sum is 38.

The square root of 7389170021 is about 85960.2816479797. The cubic root of 7389170021 is about 1947.7440508470.

Adding to 7389170021 its reverse (1200719837), we get a palindrome (8589889858).

The spelling of 7389170021 in words is "seven billion, three hundred eighty-nine million, one hundred seventy thousand, twenty-one".