51406909 has 4 divisors (see below), whose sum is σ = 53642016. Its totient is φ = 49171804.

The previous prime is 51406903. The next prime is 51406919. The reversal of 51406909 is 90960415.

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 51406909 - 2⁷ = 51406781 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 (51406903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1117519 + ... + 1117564.

It is an arithmetic number, because the mean of its divisors is an integer number (13410504).

Almost surely, 2^51406909 is an apocalyptic number.

It is an amenable number.

51406909 is a deficient number, since it is larger than the sum of its proper divisors (2235107).

51406909 is a wasteful number, since it uses less digits than its factorization.

51406909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2235106.

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 51406909 is about 7169.8611562568. The cubic root of 51406909 is about 371.8266356988.

The spelling of 51406909 in words is "fifty-one million, four hundred six thousand, nine hundred nine".