51020191 has 8 divisors (see below), whose sum is σ = 52185600. Its totient is φ = 49864920.

The previous prime is 51020173. The next prime is 51020197. The reversal of 51020191 is 19102015.

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 51020191 - 2⁷ = 51020063 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 (51020197) 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, 8146 + ... + 12976.

It is an arithmetic number, because the mean of its divisors is an integer number (6523200).

Almost surely, 2^51020191 is an apocalyptic number.

51020191 is a deficient number, since it is larger than the sum of its proper divisors (1165409).

51020191 is a wasteful number, since it uses less digits than its factorization.

51020191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5069.

The product of its (nonzero) digits is 90, while the sum is 19.

The square root of 51020191 is about 7142.8419414124. The cubic root of 51020191 is about 370.8919096236.

The spelling of 51020191 in words is "fifty-one million, twenty thousand, one hundred ninety-one".