51791489 has 4 divisors (see below), whose sum is σ = 52199424. Its totient is φ = 51383556.

The previous prime is 51791471. The next prime is 51791491. The reversal of 51791489 is 98419715.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51791489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51791449) 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, 203777 + ... + 204030.

It is an arithmetic number, because the mean of its divisors is an integer number (13049856).

Almost surely, 2^51791489 is an apocalyptic number.

It is an amenable number.

51791489 is a deficient number, since it is larger than the sum of its proper divisors (407935).

51791489 is a wasteful number, since it uses less digits than its factorization.

51791489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407934.

The product of its digits is 90720, while the sum is 44.

The square root of 51791489 is about 7196.6303920654. The cubic root of 51791489 is about 372.7515565795.

The spelling of 51791489 in words is "fifty-one million, seven hundred ninety-one thousand, four hundred eighty-nine".