251544142 has 4 divisors (see below), whose sum is σ = 377316216. Its totient is φ = 125772070.

The previous prime is 251544131. The next prime is 251544149. The reversal of 251544142 is 241445152.

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

It is a self number, because there is not a number n which added to its sum of digits gives 251544142.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251544149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 62886034 + ... + 62886037.

It is an arithmetic number, because the mean of its divisors is an integer number (94329054).

Almost surely, 2^251544142 is an apocalyptic number.

251544142 is a deficient number, since it is larger than the sum of its proper divisors (125772074).

251544142 is a wasteful number, since it uses less digits than its factorization.

251544142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125772073.

The product of its digits is 6400, while the sum is 28.

The square root of 251544142 is about 15860.1431897698. The cubic root of 251544142 is about 631.2548617473.

Adding to 251544142 its reverse (241445152), we get a palindrome (492989294).

The spelling of 251544142 in words is "two hundred fifty-one million, five hundred forty-four thousand, one hundred forty-two".