142121999 has 4 divisors (see below), whose sum is σ = 142544064. Its totient is φ = 141699936.

The previous prime is 142121983. The next prime is 142122007. The reversal of 142121999 is 999121241.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 142121999 - 2⁴ = 142121983 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 (142121909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210527 + ... + 211200.

It is an arithmetic number, because the mean of its divisors is an integer number (35636016).

Almost surely, 2^142121999 is an apocalyptic number.

142121999 is a deficient number, since it is larger than the sum of its proper divisors (422065).

142121999 is an equidigital number, since it uses as much as digits as its factorization.

142121999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 422064.

The product of its digits is 11664, while the sum is 38.

The square root of 142121999 is about 11921.4931531247. The cubic root of 142121999 is about 521.8597106401.

The spelling of 142121999 in words is "one hundred forty-two million, one hundred twenty-one thousand, nine hundred ninety-nine".