442140781 has 2 divisors, whose sum is σ = 442140782. Its totient is φ = 442140780.

The previous prime is 442140763. The next prime is 442140793. The reversal of 442140781 is 187041244.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 427248900 + 14891881 = 20670^2 + 3859^2 .

It is a cyclic number.

It is not a de Polignac number, because 442140781 - 2¹¹ = 442138733 is a prime.

It is a super-2 number, since 2×442140781² = 390976940446579922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (442120781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 221070390 + 221070391.

It is an arithmetic number, because the mean of its divisors is an integer number (221070391).

Almost surely, 2^442140781 is an apocalyptic number.

It is an amenable number.

442140781 is a deficient number, since it is larger than the sum of its proper divisors (1).

442140781 is an equidigital number, since it uses as much as digits as its factorization.

442140781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7168, while the sum is 31.

The square root of 442140781 is about 21027.1439097182. The cubic root of 442140781 is about 761.8220255422.

The spelling of 442140781 in words is "four hundred forty-two million, one hundred forty thousand, seven hundred eighty-one".