1666287798 has 32 divisors (see below), whose sum is σ = 3836071680. Its totient is φ = 472655520.

The previous prime is 1666287787. The next prime is 1666287803. The reversal of 1666287798 is 8977826661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 136873 + ... + 148548.

It is an arithmetic number, because the mean of its divisors is an integer number (119877240).

Almost surely, 2^1666287798 is an apocalyptic number.

1666287798 is an abundant number, since it is smaller than the sum of its proper divisors (2169783882).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1666287798 is a wasteful number, since it uses less digits than its factorization.

1666287798 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285572.

The product of its digits is 12192768, while the sum is 60.

The square root of 1666287798 is about 40820.1886080895. The cubic root of 1666287798 is about 1185.5412549934.

The spelling of 1666287798 in words is "one billion, six hundred sixty-six million, two hundred eighty-seven thousand, seven hundred ninety-eight".