61648809 has 16 divisors (see below), whose sum is σ = 88732800. Its totient is φ = 37955456.

The previous prime is 61648759. The next prime is 61648813. The reversal of 61648809 is 90884616.

It is a cyclic number.

It is not a de Polignac number, because 61648809 - 2²⁰ = 60600233 is a prime.

It is a super-2 number, since 2×61648809² = 7601151302236962, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61648849) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13404 + ... + 17405.

It is an arithmetic number, because the mean of its divisors is an integer number (5545800).

Almost surely, 2^61648809 is an apocalyptic number.

61648809 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

It is an amenable number.

61648809 is a deficient number, since it is larger than the sum of its proper divisors (27083991).

61648809 is a wasteful number, since it uses less digits than its factorization.

61648809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30864.

The product of its (nonzero) digits is 82944, while the sum is 42.

The square root of 61648809 is about 7851.6755536637. The cubic root of 61648809 is about 395.0404466407.

The spelling of 61648809 in words is "sixty-one million, six hundred forty-eight thousand, eight hundred nine".