51540443 has 4 divisors (see below), whose sum is σ = 51693720. Its totient is φ = 51387168.

The previous prime is 51540439. The next prime is 51540451. The reversal of 51540443 is 34404515.

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

It is a cyclic number.

It is not a de Polignac number, because 51540443 - 2² = 51540439 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51540043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 76133 + ... + 76806.

It is an arithmetic number, because the mean of its divisors is an integer number (12923430).

Almost surely, 2^51540443 is an apocalyptic number.

51540443 is a deficient number, since it is larger than the sum of its proper divisors (153277).

51540443 is a wasteful number, since it uses less digits than its factorization.

51540443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153276.

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 51540443 is about 7179.1672915457. The cubic root of 51540443 is about 372.1483082099.

Adding to 51540443 its reverse (34404515), we get a palindrome (85944958).

The spelling of 51540443 in words is "fifty-one million, five hundred forty thousand, four hundred forty-three".