20257142 has 4 divisors (see below), whose sum is σ = 30385716. Its totient is φ = 10128570.

The previous prime is 20257121. The next prime is 20257163. The reversal of 20257142 is 24175202.

It is a happy number.

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

It is an interprime number because it is at equal distance from previous prime (20257121) and next prime (20257163).

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5064284 + ... + 5064287.

It is an arithmetic number, because the mean of its divisors is an integer number (7596429).

Almost surely, 2^20257142 is an apocalyptic number.

20257142 is a deficient number, since it is larger than the sum of its proper divisors (10128574).

20257142 is a wasteful number, since it uses less digits than its factorization.

20257142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10128573.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 20257142 is about 4500.7934855978. The cubic root of 20257142 is about 272.6001292948.

The spelling of 20257142 in words is "twenty million, two hundred fifty-seven thousand, one hundred forty-two".