51781471 has 4 divisors (see below), whose sum is σ = 59178832. Its totient is φ = 44384112.

The previous prime is 51781453. The next prime is 51781481. The reversal of 51781471 is 17418715.

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 51781471 - 2⁷ = 51781343 is a prime.

It is a super-3 number, since 3×51781471³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51781421) 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, 3698670 + ... + 3698683.

It is an arithmetic number, because the mean of its divisors is an integer number (14794708).

Almost surely, 2^51781471 is an apocalyptic number.

51781471 is a deficient number, since it is larger than the sum of its proper divisors (7397361).

51781471 is an equidigital number, since it uses as much as digits as its factorization.

51781471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7397360.

The product of its digits is 7840, while the sum is 34.

The square root of 51781471 is about 7195.9343382218. The cubic root of 51781471 is about 372.7275213183.

The spelling of 51781471 in words is "fifty-one million, seven hundred eighty-one thousand, four hundred seventy-one".