1994045861 has 4 divisors (see below), whose sum is σ = 2002830432. Its totient is φ = 1985261292.

The previous prime is 1994045827. The next prime is 1994045899. The reversal of 1994045861 is 1685404991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1994045861 - 2⁶ = 1994045797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1994065861) 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 in 3 ways as a sum of consecutive naturals, for example, 4391945 + ... + 4392398.

It is an arithmetic number, because the mean of its divisors is an integer number (500707608).

Almost surely, 2^1994045861 is an apocalyptic number.

It is an amenable number.

1994045861 is a deficient number, since it is larger than the sum of its proper divisors (8784571).

1994045861 is an equidigital number, since it uses as much as digits as its factorization.

1994045861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8784570.

The product of its (nonzero) digits is 311040, while the sum is 47.

The square root of 1994045861 is about 44654.7406329944. The cubic root of 1994045861 is about 1258.6695162611.

The spelling of 1994045861 in words is "one billion, nine hundred ninety-four million, forty-five thousand, eight hundred sixty-one".