20995042 has 4 divisors (see below), whose sum is σ = 31492566. Its totient is φ = 10497520.

The previous prime is 20995031. The next prime is 20995063. The reversal of 20995042 is 24059902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24059902 = 2 ⋅12029951.

It can be written as a sum of positive squares in only one way, i.e., 11015761 + 9979281 = 3319^2 + 3159^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a junction number, because it is equal to n+sod(n) for n = 20994995 and 20995013.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5248759 + ... + 5248762.

Almost surely, 2^20995042 is an apocalyptic number.

20995042 is a deficient number, since it is larger than the sum of its proper divisors (10497524).

20995042 is a wasteful number, since it uses less digits than its factorization.

20995042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10497523.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 20995042 is about 4582.0347008725. The cubic root of 20995042 is about 275.8707036338.

It can be divided in two parts, 209950 and 42, that multiplied together give a triangular number (8817900 = T₄₁₉₉).

The spelling of 20995042 in words is "twenty million, nine hundred ninety-five thousand, forty-two".