57406781 has 4 divisors (see below), whose sum is σ = 59902752. Its totient is φ = 54910812.

The previous prime is 57406777. The next prime is 57406793. The reversal of 57406781 is 18760475.

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 57406781 - 2² = 57406777 is a prime.

It is a super-2 number, since 2×57406781² = 6591077009563922, 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 (57406081) 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, 1247951 + ... + 1247996.

It is an arithmetic number, because the mean of its divisors is an integer number (14975688).

Almost surely, 2^57406781 is an apocalyptic number.

It is an amenable number.

57406781 is a deficient number, since it is larger than the sum of its proper divisors (2495971).

57406781 is a wasteful number, since it uses less digits than its factorization.

57406781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2495970.

The product of its (nonzero) digits is 47040, while the sum is 38.

The square root of 57406781 is about 7576.7262719462. The cubic root of 57406781 is about 385.7634393103.

It can be divided in two parts, 5740 and 6781, that added together give a palindrome (12521).

The spelling of 57406781 in words is "fifty-seven million, four hundred six thousand, seven hundred eighty-one".