199942145 has 16 divisors (see below), whose sum is σ = 259413840. Its totient is φ = 147062784.

The previous prime is 199942139. The next prime is 199942159. The reversal of 199942145 is 541249991.

It can be written as a sum of positive squares in 8 ways, for example, as 6370576 + 193571569 = 2524^2 + 13913^2 .

It is a cyclic number.

It is not a de Polignac number, because 199942145 - 2⁶ = 199942081 is a prime.

It is a super-2 number, since 2×199942145² = 79953722694402050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 199942096 and 199942105.

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, 10721 + ... + 22689.

It is an arithmetic number, because the mean of its divisors is an integer number (16213365).

Almost surely, 2^199942145 is an apocalyptic number.

It is an amenable number.

199942145 is a deficient number, since it is larger than the sum of its proper divisors (59471695).

199942145 is a wasteful number, since it uses less digits than its factorization.

199942145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12244.

The product of its digits is 116640, while the sum is 44.

The square root of 199942145 is about 14140.0899926415. The cubic root of 199942145 is about 584.7471525222.

It can be divided in two parts, 1999 and 42145, that added together give a palindrome (44144).

The spelling of 199942145 in words is "one hundred ninety-nine million, nine hundred forty-two thousand, one hundred forty-five".