61851891 has 8 divisors (see below), whose sum is σ = 82561680. Its totient is φ = 41188352.

The previous prime is 61851887. The next prime is 61851929. The reversal of 61851891 is 19815816.

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

It is a cyclic number.

It is not a de Polignac number, because 61851891 - 2² = 61851887 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61851791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8310 + ... + 13883.

It is an arithmetic number, because the mean of its divisors is an integer number (10320210).

Almost surely, 2^61851891 is an apocalyptic number.

61851891 is a deficient number, since it is larger than the sum of its proper divisors (20709789).

61851891 is a wasteful number, since it uses less digits than its factorization.

61851891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23125.

The product of its digits is 17280, while the sum is 39.

The square root of 61851891 is about 7864.5973196344. The cubic root of 61851891 is about 395.4737487258.

The spelling of 61851891 in words is "sixty-one million, eight hundred fifty-one thousand, eight hundred ninety-one".