1391520749 has 2 divisors, whose sum is σ = 1391520750. Its totient is φ = 1391520748.

The previous prime is 1391520743. The next prime is 1391520791. The reversal of 1391520749 is 9470251931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1125602500 + 265918249 = 33550^2 + 16307^2 .

It is a cyclic number.

It is not a de Polignac number, because 1391520749 - 2¹⁶ = 1391455213 is a prime.

It is a super-3 number, since 3×1391520749³ (a number of 28 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1391520743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 695760374 + 695760375.

It is an arithmetic number, because the mean of its divisors is an integer number (695760375).

Almost surely, 2^1391520749 is an apocalyptic number.

It is an amenable number.

1391520749 is a deficient number, since it is larger than the sum of its proper divisors (1).

1391520749 is an equidigital number, since it uses as much as digits as its factorization.

1391520749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68040, while the sum is 41.

The square root of 1391520749 is about 37303.0930218930. The cubic root of 1391520749 is about 1116.4258803422.

The spelling of 1391520749 in words is "one billion, three hundred ninety-one million, five hundred twenty thousand, seven hundred forty-nine".