51908609 has 4 divisors (see below), whose sum is σ = 52565760. Its totient is φ = 51251460.

The previous prime is 51908569. The next prime is 51908617. The reversal of 51908609 is 90680915.

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 not a de Polignac number, because 51908609 - 2¹⁶ = 51843073 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51908509) 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, 328457 + ... + 328614.

It is an arithmetic number, because the mean of its divisors is an integer number (13141440).

Almost surely, 2^51908609 is an apocalyptic number.

It is an amenable number.

51908609 is a deficient number, since it is larger than the sum of its proper divisors (657151).

51908609 is an equidigital number, since it uses as much as digits as its factorization.

51908609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657150.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 51908609 is about 7204.7629385012. The cubic root of 51908609 is about 373.0323221157.

The spelling of 51908609 in words is "fifty-one million, nine hundred eight thousand, six hundred nine".