61887709 has 8 divisors (see below), whose sum is σ = 66738392. Its totient is φ = 57049920.

The previous prime is 61887703. The next prime is 61887719. The reversal of 61887709 is 90778816.

It can be written as a sum of positive squares in 4 ways, for example, as 1747684 + 60140025 = 1322^2 + 7755^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61887709 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 (61887703) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8299 + ... + 13879.

It is an arithmetic number, because the mean of its divisors is an integer number (8342299).

Almost surely, 2^61887709 is an apocalyptic number.

It is an amenable number.

61887709 is a deficient number, since it is larger than the sum of its proper divisors (4850683).

61887709 is a wasteful number, since it uses less digits than its factorization.

61887709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6447.

The product of its (nonzero) digits is 169344, while the sum is 46.

The square root of 61887709 is about 7866.8741568682. The cubic root of 61887709 is about 395.5500726941.

The spelling of 61887709 in words is "sixty-one million, eight hundred eighty-seven thousand, seven hundred nine".