51780393 has 12 divisors (see below), whose sum is σ = 85478848. Its totient is φ = 29588760.

The previous prime is 51780389. The next prime is 51780401. The reversal of 51780393 is 39308715.

It is not a de Polignac number, because 51780393 - 2² = 51780389 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51780343) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 410893 + ... + 411018.

Almost surely, 2^51780393 is an apocalyptic number.

It is an amenable number.

51780393 is a deficient number, since it is larger than the sum of its proper divisors (33698455).

51780393 is a wasteful number, since it uses less digits than its factorization.

51780393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821924 (or 821921 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 51780393 is about 7195.8594344248. The cubic root of 51780393 is about 372.7249347879.

The spelling of 51780393 in words is "fifty-one million, seven hundred eighty thousand, three hundred ninety-three".