61386809 has 6 divisors (see below), whose sum is σ = 67474890. Its totient is φ = 55806080.

The previous prime is 61386803. The next prime is 61386821. The reversal of 61386809 is 90868316.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 36336784 + 25050025 = 6028^2 + 5005^2 .

It is not a de Polignac number, because 61386809 - 2²⁰ = 60338233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61386803) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 253544 + ... + 253785.

It is an arithmetic number, because the mean of its divisors is an integer number (11245815).

Almost surely, 2^61386809 is an apocalyptic number.

It is an amenable number.

61386809 is a deficient number, since it is larger than the sum of its proper divisors (6088081).

61386809 is a wasteful number, since it uses less digits than its factorization.

61386809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507351 (or 507340 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 41.

The square root of 61386809 is about 7834.9734524119. The cubic root of 61386809 is about 394.4800272396.

The spelling of 61386809 in words is "sixty-one million, three hundred eighty-six thousand, eight hundred nine".