51551409 has 16 divisors (see below), whose sum is σ = 84597632. Its totient is φ = 27191808.

The previous prime is 51551407. The next prime is 51551431. The reversal of 51551409 is 90415515.

It is not a de Polignac number, because 51551409 - 2¹ = 51551407 is a prime.

It is not an unprimeable number, because it can be changed into a prime (51551407) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 94144 + ... + 94689.

It is an arithmetic number, because the mean of its divisors is an integer number (5287352).

Almost surely, 2^51551409 is an apocalyptic number.

It is an amenable number.

51551409 is a deficient number, since it is larger than the sum of its proper divisors (33046223).

51551409 is a wasteful number, since it uses less digits than its factorization.

51551409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188856.

The product of its (nonzero) digits is 4500, while the sum is 30.

The square root of 51551409 is about 7179.9309885263. The cubic root of 51551409 is about 372.1746997109.

The spelling of 51551409 in words is "fifty-one million, five hundred fifty-one thousand, four hundred nine".