1382287721 has 2 divisors, whose sum is σ = 1382287722. Its totient is φ = 1382287720.

The previous prime is 1382287691. The next prime is 1382287723. The reversal of 1382287721 is 1277822831.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 859662400 + 522625321 = 29320^2 + 22861^2 .

It is an emirp because it is prime and its reverse (1277822831) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1382287721 - 2⁶ = 1382287657 is a prime.

Together with 1382287723, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1382287723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 691143860 + 691143861.

It is an arithmetic number, because the mean of its divisors is an integer number (691143861).

Almost surely, 2^1382287721 is an apocalyptic number.

It is an amenable number.

1382287721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1382287721 is an equidigital number, since it uses as much as digits as its factorization.

1382287721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75264, while the sum is 41.

The square root of 1382287721 is about 37179.1301807883. The cubic root of 1382287721 is about 1113.9511599361.

The spelling of 1382287721 in words is "one billion, three hundred eighty-two million, two hundred eighty-seven thousand, seven hundred twenty-one".