1990523 has 2 divisors, whose sum is σ = 1990524. Its totient is φ = 1990522.

The previous prime is 1990507. The next prime is 1990529. The reversal of 1990523 is 3250991.

It is a strong prime.

It is an emirp because it is prime and its reverse (3250991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1990523 - 2⁴ = 1990507 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1990529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995261 + 995262.

It is an arithmetic number, because the mean of its divisors is an integer number (995262).

2^1990523 is an apocalyptic number.

1990523 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990523 is an equidigital number, since it uses as much as digits as its factorization.

1990523 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2430, while the sum is 29.

The square root of 1990523 is about 1410.8589582237. The cubic root of 1990523 is about 125.7927853019.

The spelling of 1990523 in words is "one million, nine hundred ninety thousand, five hundred twenty-three".