51852781 has 4 divisors (see below), whose sum is σ = 51887200. Its totient is φ = 51818364.

The previous prime is 51852751. The next prime is 51852793. The reversal of 51852781 is 18725815.

51852781 = T₅₈₇₈ + T₅₈₇₉ + T₅₈₈₀.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18725815 = 5 ⋅3745163.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51852781 is a prime.

It is a super-2 number, since 2×51852781² = 5377421794867922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51852781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51852701) 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, 14841 + ... + 17998.

It is an arithmetic number, because the mean of its divisors is an integer number (12971800).

Almost surely, 2^51852781 is an apocalyptic number.

51852781 is the 5880-th centered triangular number.

It is an amenable number.

51852781 is a deficient number, since it is larger than the sum of its proper divisors (34419).

51852781 is a wasteful number, since it uses less digits than its factorization.

51852781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34418.

The product of its digits is 22400, while the sum is 37.

The square root of 51852781 is about 7200.8875147443. The cubic root of 51852781 is about 372.8985413590.

The spelling of 51852781 in words is "fifty-one million, eight hundred fifty-two thousand, seven hundred eighty-one".