442520389 has 2 divisors, whose sum is σ = 442520390. Its totient is φ = 442520388.

The previous prime is 442520363. The next prime is 442520401. The reversal of 442520389 is 983025244.

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., 405821025 + 36699364 = 20145^2 + 6058^2 .

It is a cyclic number.

It is not a de Polignac number, because 442520389 - 2¹⁹ = 441996101 is a prime.

It is a super-2 number, since 2×442520389² = 391648589361422642, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (442529389) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 221260194 + 221260195.

It is an arithmetic number, because the mean of its divisors is an integer number (221260195).

Almost surely, 2^442520389 is an apocalyptic number.

It is an amenable number.

442520389 is a deficient number, since it is larger than the sum of its proper divisors (1).

442520389 is an equidigital number, since it uses as much as digits as its factorization.

442520389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69120, while the sum is 37.

The square root of 442520389 is about 21036.1685912621. The cubic root of 442520389 is about 762.0399885555.

The spelling of 442520389 in words is "four hundred forty-two million, five hundred twenty thousand, three hundred eighty-nine".