42640529 has 4 divisors (see below), whose sum is σ = 42681780. Its totient is φ = 42599280.

The previous prime is 42640517. The next prime is 42640553. The reversal of 42640529 is 92504624.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11022400 + 31618129 = 3320^2 + 5623^2 .

It is a cyclic number.

It is not a de Polignac number, because 42640529 - 2⁴ = 42640513 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 42640495 and 42640504.

It is not an unprimeable number, because it can be changed into a prime (42645529) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19034 + ... + 21155.

It is an arithmetic number, because the mean of its divisors is an integer number (10670445).

Almost surely, 2^42640529 is an apocalyptic number.

It is an amenable number.

42640529 is a deficient number, since it is larger than the sum of its proper divisors (41251).

42640529 is a wasteful number, since it uses less digits than its factorization.

42640529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41250.

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 42640529 is about 6529.9715925875. The cubic root of 42640529 is about 349.3608170846.

The spelling of 42640529 in words is "forty-two million, six hundred forty thousand, five hundred twenty-nine".