61087809 has 4 divisors (see below), whose sum is σ = 81450416. Its totient is φ = 40725204.

The previous prime is 61087801. The next prime is 61087823. The reversal of 61087809 is 90878016.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 61087809 - 2³ = 61087801 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61087801) 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, 10181299 + ... + 10181304.

It is an arithmetic number, because the mean of its divisors is an integer number (20362604).

Almost surely, 2^61087809 is an apocalyptic number.

It is an amenable number.

61087809 is a deficient number, since it is larger than the sum of its proper divisors (20362607).

61087809 is a wasteful number, since it uses less digits than its factorization.

61087809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20362606.

The product of its (nonzero) digits is 24192, while the sum is 39.

The square root of 61087809 is about 7815.8690495683. The cubic root of 61087809 is about 393.8385129307.

The spelling of 61087809 in words is "sixty-one million, eighty-seven thousand, eight hundred nine".