1990151 has 2 divisors, whose sum is σ = 1990152. Its totient is φ = 1990150.

The previous prime is 1990147. The next prime is 1990159. The reversal of 1990151 is 1510991.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1510991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1990151 - 2² = 1990147 is a prime.

It is a Sophie Germain prime.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1990151.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1990159) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995075 + 995076.

It is an arithmetic number, because the mean of its divisors is an integer number (995076).

2^1990151 is an apocalyptic number.

1990151 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990151 is an equidigital number, since it uses as much as digits as its factorization.

1990151 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 405, while the sum is 26.

The square root of 1990151 is about 1410.7271174823. The cubic root of 1990151 is about 125.7849485288.

The spelling of 1990151 in words is "one million, nine hundred ninety thousand, one hundred fifty-one".