51408397 has 4 divisors (see below), whose sum is σ = 51556896. Its totient is φ = 51259900.

The previous prime is 51408389. The next prime is 51408431. The reversal of 51408397 is 79380415.

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 51408397 - 2³ = 51408389 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 (51408337) 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, 73729 + ... + 74422.

It is an arithmetic number, because the mean of its divisors is an integer number (12889224).

Almost surely, 2^51408397 is an apocalyptic number.

It is an amenable number.

51408397 is a deficient number, since it is larger than the sum of its proper divisors (148499).

51408397 is a wasteful number, since it uses less digits than its factorization.

51408397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148498.

The product of its (nonzero) digits is 30240, while the sum is 37.

The square root of 51408397 is about 7169.9649232057. The cubic root of 51408397 is about 371.8302232367.

The spelling of 51408397 in words is "fifty-one million, four hundred eight thousand, three hundred ninety-seven".