1990215923 has 2 divisors, whose sum is σ = 1990215924. Its totient is φ = 1990215922.

The previous prime is 1990215919. The next prime is 1990215937. The reversal of 1990215923 is 3295120991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1990215923 - 2² = 1990215919 is a prime.

It is not a weakly prime, because it can be changed into another prime (1990215023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995107961 + 995107962.

It is an arithmetic number, because the mean of its divisors is an integer number (995107962).

Almost surely, 2^1990215923 is an apocalyptic number.

1990215923 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990215923 is an equidigital number, since it uses as much as digits as its factorization.

1990215923 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 43740, while the sum is 41.

The square root of 1990215923 is about 44611.8361312332. The cubic root of 1990215923 is about 1257.8631630563.

The spelling of 1990215923 in words is "one billion, nine hundred ninety million, two hundred fifteen thousand, nine hundred twenty-three".