51431487 has 4 divisors (see below), whose sum is σ = 68575320. Its totient is φ = 34287656.

The previous prime is 51431467. The next prime is 51431503. The reversal of 51431487 is 78413415.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 51431487 - 2¹¹ = 51429439 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51431407) 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, 8571912 + ... + 8571917.

It is an arithmetic number, because the mean of its divisors is an integer number (17143830).

Almost surely, 2^51431487 is an apocalyptic number.

51431487 is a deficient number, since it is larger than the sum of its proper divisors (17143833).

51431487 is a wasteful number, since it uses less digits than its factorization.

51431487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17143832.

The product of its digits is 13440, while the sum is 33.

The square root of 51431487 is about 7171.5749316311. The cubic root of 51431487 is about 371.8858838893.

The spelling of 51431487 in words is "fifty-one million, four hundred thirty-one thousand, four hundred eighty-seven".