1990551443 has 2 divisors, whose sum is σ = 1990551444. Its totient is φ = 1990551442.

The previous prime is 1990551349. The next prime is 1990551469. The reversal of 1990551443 is 3441550991.

It is a strong prime.

It is an emirp because it is prime and its reverse (3441550991) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1990551443 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1990551443.

It is not a weakly prime, because it can be changed into another prime (1990521443) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995275721 + 995275722.

It is an arithmetic number, because the mean of its divisors is an integer number (995275722).

Almost surely, 2^1990551443 is an apocalyptic number.

1990551443 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990551443 is an equidigital number, since it uses as much as digits as its factorization.

1990551443 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 97200, while the sum is 41.

The square root of 1990551443 is about 44615.5964097758. The cubic root of 1990551443 is about 1257.9338445887.

The spelling of 1990551443 in words is "one billion, nine hundred ninety million, five hundred fifty-one thousand, four hundred forty-three".