1539997 has 2 divisors, whose sum is σ = 1539998. Its totient is φ = 1539996.

The previous prime is 1539991. The next prime is 1540003. The reversal of 1539997 is 7999351.

It is a balanced prime because it is at equal distance from previous prime (1539991) and next prime (1540003).

It can be written as a sum of positive squares in only one way, i.e., 933156 + 606841 = 966^2 + 779^2 .

It is an emirp because it is prime and its reverse (7999351) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1539997 - 2⁷ = 1539869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1539991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 769998 + 769999.

It is an arithmetic number, because the mean of its divisors is an integer number (769999).

2^1539997 is an apocalyptic number.

It is an amenable number.

1539997 is a deficient number, since it is larger than the sum of its proper divisors (1).

1539997 is an equidigital number, since it uses as much as digits as its factorization.

1539997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 76545, while the sum is 43.

The square root of 1539997 is about 1240.9661558641. The cubic root of 1539997 is about 115.4799600421.

The spelling of 1539997 in words is "one million, five hundred thirty-nine thousand, nine hundred ninety-seven".