78100061 has 4 divisors (see below), whose sum is σ = 84107772. Its totient is φ = 72092352.

The previous prime is 78100021. The next prime is 78100097. The reversal of 78100061 is 16000187.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16000187 = 7 ⋅2285741.

It can be written as a sum of positive squares in 2 ways, for example, as 17556100 + 60543961 = 4190^2 + 7781^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78100061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78100021) 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, 3003836 + ... + 3003861.

It is an arithmetic number, because the mean of its divisors is an integer number (21026943).

Almost surely, 2^78100061 is an apocalyptic number.

It is an amenable number.

78100061 is a deficient number, since it is larger than the sum of its proper divisors (6007711).

78100061 is a wasteful number, since it uses less digits than its factorization.

78100061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6007710.

The product of its (nonzero) digits is 336, while the sum is 23.

The square root of 78100061 is about 8837.4238893469. The cubic root of 78100061 is about 427.4484937319.

The spelling of 78100061 in words is "seventy-eight million, one hundred thousand, sixty-one".