42451381 has 4 divisors (see below), whose sum is σ = 48515872. Its totient is φ = 36386892.

The previous prime is 42451373. The next prime is 42451393. The reversal of 42451381 is 18315424.

42451381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 42451381 - 2³ = 42451373 is a prime.

It is a super-2 number, since 2×42451381² = 3604239497614322, 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 (42452381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3032235 + ... + 3032248.

It is an arithmetic number, because the mean of its divisors is an integer number (12128968).

Almost surely, 2^42451381 is an apocalyptic number.

It is an amenable number.

42451381 is a deficient number, since it is larger than the sum of its proper divisors (6064491).

42451381 is an equidigital number, since it uses as much as digits as its factorization.

42451381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6064490.

The product of its digits is 3840, while the sum is 28.

The square root of 42451381 is about 6515.4724310675. The cubic root of 42451381 is about 348.8434778948.

The spelling of 42451381 in words is "forty-two million, four hundred fifty-one thousand, three hundred eighty-one".