51440146 has 4 divisors (see below), whose sum is σ = 77160222. Its totient is φ = 25720072.

The previous prime is 51440111. The next prime is 51440149. The reversal of 51440146 is 64104415.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 64104415 = 5 ⋅12820883.

It can be written as a sum of positive squares in only one way, i.e., 42107121 + 9333025 = 6489^2 + 3055^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 51440146.

It is not an unprimeable number, because it can be changed into a prime (51440149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12860035 + ... + 12860038.

Almost surely, 2^51440146 is an apocalyptic number.

51440146 is a deficient number, since it is larger than the sum of its proper divisors (25720076).

51440146 is a wasteful number, since it uses less digits than its factorization.

51440146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25720075.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 51440146 is about 7172.1786090420. The cubic root of 51440146 is about 371.9067529415.

The spelling of 51440146 in words is "fifty-one million, four hundred forty thousand, one hundred forty-six".