57781331 has 2 divisors, whose sum is σ = 57781332. Its totient is φ = 57781330.

The previous prime is 57781319. The next prime is 57781417. The reversal of 57781331 is 13318775.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 57781331 - 2¹⁴ = 57764947 is a prime.

It is a super-2 number, since 2×57781331² = 6677364424263122, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 57781291 and 57781300.

It is not a weakly prime, because it can be changed into another prime (57781631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28890665 + 28890666.

It is an arithmetic number, because the mean of its divisors is an integer number (28890666).

Almost surely, 2^57781331 is an apocalyptic number.

57781331 is a deficient number, since it is larger than the sum of its proper divisors (1).

57781331 is an equidigital number, since it uses as much as digits as its factorization.

57781331 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17640, while the sum is 35.

The square root of 57781331 is about 7601.4032257209. The cubic root of 57781331 is about 386.6005912493.

The spelling of 57781331 in words is "fifty-seven million, seven hundred eighty-one thousand, three hundred thirty-one".