51861523 has 4 divisors (see below), whose sum is σ = 59270320. Its totient is φ = 44452728.

The previous prime is 51861503. The next prime is 51861533. The reversal of 51861523 is 32516815.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51861523 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51861503) 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, 3704388 + ... + 3704401.

It is an arithmetic number, because the mean of its divisors is an integer number (14817580).

Almost surely, 2^51861523 is an apocalyptic number.

51861523 is a deficient number, since it is larger than the sum of its proper divisors (7408797).

51861523 is an equidigital number, since it uses as much as digits as its factorization.

51861523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7408796.

The product of its digits is 7200, while the sum is 31.

The square root of 51861523 is about 7201.4944976720. The cubic root of 51861523 is about 372.9194961713.

The spelling of 51861523 in words is "fifty-one million, eight hundred sixty-one thousand, five hundred twenty-three".