42615409 has 4 divisors (see below), whose sum is σ = 42629860. Its totient is φ = 42600960.

The previous prime is 42615401. The next prime is 42615431. The reversal of 42615409 is 90451624.

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 23736384 + 18879025 = 4872^2 + 4345^2 .

It is a cyclic number.

It is not a de Polignac number, because 42615409 - 2³ = 42615401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42615401) 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, 1032 + ... + 9289.

It is an arithmetic number, because the mean of its divisors is an integer number (10657465).

Almost surely, 2^42615409 is an apocalyptic number.

42615409 is the 4129-th heptagonal number.

It is an amenable number.

42615409 is a deficient number, since it is larger than the sum of its proper divisors (14451).

42615409 is a wasteful number, since it uses less digits than its factorization.

42615409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14450.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 42615409 is about 6528.0478705353. The cubic root of 42615409 is about 349.2921995211.

The spelling of 42615409 in words is "forty-two million, six hundred fifteen thousand, four hundred nine".