442781645 has 8 divisors (see below), whose sum is σ = 532384920. Its totient is φ = 353527360.

The previous prime is 442781641. The next prime is 442781659. The reversal of 442781645 is 546187244.

It can be written as a sum of positive squares in 4 ways, for example, as 123587689 + 319193956 = 11117^2 + 17866^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 442781645 - 2² = 442781641 is a prime.

It is a super-3 number, since 3×442781645³ (a number of 27 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (442781641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84446 + ... + 89535.

It is an arithmetic number, because the mean of its divisors is an integer number (66548115).

Almost surely, 2^442781645 is an apocalyptic number.

It is an amenable number.

442781645 is a deficient number, since it is larger than the sum of its proper divisors (89603275).

442781645 is a wasteful number, since it uses less digits than its factorization.

442781645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174495.

The product of its digits is 215040, while the sum is 41.

The square root of 442781645 is about 21042.3773609352. The cubic root of 442781645 is about 762.1899239090.

The spelling of 442781645 in words is "four hundred forty-two million, seven hundred eighty-one thousand, six hundred forty-five".