61864009 has 4 divisors (see below), whose sum is σ = 62007316. Its totient is φ = 61720704.

The previous prime is 61864007. The next prime is 61864051. The reversal of 61864009 is 90046816.

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 30470400 + 31393609 = 5520^2 + 5603^2 .

It is a cyclic number.

It is not a de Polignac number, because 61864009 - 2¹ = 61864007 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61864001) 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, 71004 + ... + 71869.

It is an arithmetic number, because the mean of its divisors is an integer number (15501829).

Almost surely, 2^61864009 is an apocalyptic number.

It is an amenable number.

61864009 is a deficient number, since it is larger than the sum of its proper divisors (143307).

61864009 is a wasteful number, since it uses less digits than its factorization.

61864009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143306.

The product of its (nonzero) digits is 10368, while the sum is 34.

The square root of 61864009 is about 7865.3676964272. The cubic root of 61864009 is about 395.4995740636.

The spelling of 61864009 in words is "sixty-one million, eight hundred sixty-four thousand, nine".