21031142 has 32 divisors (see below), whose sum is σ = 37161504. Its totient is φ = 8819200.

The previous prime is 21031111. The next prime is 21031151. The reversal of 21031142 is 24113012.

It is a congruent number.

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 in 15 ways as a sum of consecutive naturals, for example, 19292 + ... + 20352.

It is an arithmetic number, because the mean of its divisors is an integer number (1161297).

Almost surely, 2^21031142 is an apocalyptic number.

21031142 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21031142 is a deficient number, since it is larger than the sum of its proper divisors (16130362).

21031142 is a wasteful number, since it uses less digits than its factorization.

21031142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1144.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21031142 is about 4585.9723069378. The cubic root of 21031142 is about 276.0287287186.

Adding to 21031142 its reverse (24113012), we get a palindrome (45144154).

The spelling of 21031142 in words is "twenty-one million, thirty-one thousand, one hundred forty-two".