251121742 has 8 divisors (see below), whose sum is σ = 376751232. Its totient is φ = 125538000.

The previous prime is 251121737. The next prime is 251121743. The reversal of 251121742 is 247121152.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×251121742² = 126124258610229128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251121743) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11442 + ... + 25162.

It is an arithmetic number, because the mean of its divisors is an integer number (47093904).

Almost surely, 2^251121742 is an apocalyptic number.

251121742 is a deficient number, since it is larger than the sum of its proper divisors (125629490).

251121742 is a wasteful number, since it uses less digits than its factorization.

251121742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22874.

The product of its digits is 1120, while the sum is 25.

The square root of 251121742 is about 15846.8211954322. The cubic root of 251121742 is about 630.9013234753.

Adding to 251121742 its reverse (247121152), we get a palindrome (498242894).

The spelling of 251121742 in words is "two hundred fifty-one million, one hundred twenty-one thousand, seven hundred forty-two".