57078781 has 4 divisors (see below), whose sum is σ = 58920064. Its totient is φ = 55237500.

The previous prime is 57078779. The next prime is 57078787. The reversal of 57078781 is 18787075.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 57078781 - 2¹ = 57078779 is a prime.

It is a super-2 number, since 2×57078781² = 6515974480891922, 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 (57078787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 920595 + ... + 920656.

It is an arithmetic number, because the mean of its divisors is an integer number (14730016).

Almost surely, 2^57078781 is an apocalyptic number.

It is an amenable number.

57078781 is a deficient number, since it is larger than the sum of its proper divisors (1841283).

57078781 is a wasteful number, since it uses less digits than its factorization.

57078781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1841282.

The product of its (nonzero) digits is 109760, while the sum is 43.

The square root of 57078781 is about 7555.0500329250. The cubic root of 57078781 is about 385.0273348782.

The spelling of 57078781 in words is "fifty-seven million, seventy-eight thousand, seven hundred eighty-one".