51720367 has 4 divisors (see below), whose sum is σ = 51801696. Its totient is φ = 51639040.

The previous prime is 51720359. The next prime is 51720373. The reversal of 51720367 is 76302715.

51720367 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 51720367 - 2³ = 51720359 is a prime.

It is a super-2 number, since 2×51720367² = 5349992725229378, which contains 22 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 (51720397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39703 + ... + 40984.

It is an arithmetic number, because the mean of its divisors is an integer number (12950424).

Almost surely, 2^51720367 is an apocalyptic number.

51720367 is a deficient number, since it is larger than the sum of its proper divisors (81329).

51720367 is an equidigital number, since it uses as much as digits as its factorization.

51720367 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 81328.

The product of its (nonzero) digits is 8820, while the sum is 31.

The square root of 51720367 is about 7191.6873541611. The cubic root of 51720367 is about 372.5808529805.

The spelling of 51720367 in words is "fifty-one million, seven hundred twenty thousand, three hundred sixty-seven".