42557381 has 2 divisors, whose sum is σ = 42557382. Its totient is φ = 42557380.

The previous prime is 42557369. The next prime is 42557393. The reversal of 42557381 is 18375524.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (42557369) and next prime (42557393).

It can be written as a sum of positive squares in only one way, i.e., 41809156 + 748225 = 6466^2 + 865^2 .

It is a cyclic number.

It is not a de Polignac number, because 42557381 - 2¹⁰ = 42556357 is a prime.

It is a super-2 number, since 2×42557381² = 3622261355158322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42557311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21278690 + 21278691.

It is an arithmetic number, because the mean of its divisors is an integer number (21278691).

Almost surely, 2^42557381 is an apocalyptic number.

It is an amenable number.

42557381 is a deficient number, since it is larger than the sum of its proper divisors (1).

42557381 is an equidigital number, since it uses as much as digits as its factorization.

42557381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 33600, while the sum is 35.

The square root of 42557381 is about 6523.6018425407. The cubic root of 42557381 is about 349.1335876094.

The spelling of 42557381 in words is "forty-two million, five hundred fifty-seven thousand, three hundred eighty-one".