1990215806 has 32 divisors (see below), whose sum is σ = 3306173760. Its totient is φ = 893730816.

The previous prime is 1990215803. The next prime is 1990215817. The reversal of 1990215806 is 6085120991.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1990215803) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 354590 + ... + 360158.

It is an arithmetic number, because the mean of its divisors is an integer number (103317930).

Almost surely, 2^1990215806 is an apocalyptic number.

1990215806 is a deficient number, since it is larger than the sum of its proper divisors (1315957954).

1990215806 is a wasteful number, since it uses less digits than its factorization.

1990215806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6068.

The product of its (nonzero) digits is 38880, while the sum is 41.

The square root of 1990215806 is about 44611.8348199219. The cubic root of 1990215806 is about 1257.8631384073.

The spelling of 1990215806 in words is "one billion, nine hundred ninety million, two hundred fifteen thousand, eight hundred six".