51349999 has 4 divisors (see below), whose sum is σ = 52602480. Its totient is φ = 50097520.

The previous prime is 51349993. The next prime is 51350003. The reversal of 51349999 is 99994315.

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 51349999 - 2⁵ = 51349967 is a prime.

It is a Duffinian number.

51349999 is a modest number, since divided by 9999 gives 5134 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51349993) 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, 626179 + ... + 626260.

It is an arithmetic number, because the mean of its divisors is an integer number (13150620).

Almost surely, 2^51349999 is an apocalyptic number.

51349999 is a deficient number, since it is larger than the sum of its proper divisors (1252481).

51349999 is a wasteful number, since it uses less digits than its factorization.

51349999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1252480.

The product of its digits is 393660, while the sum is 49.

The square root of 51349999 is about 7165.8913611637. The cubic root of 51349999 is about 371.6893748540.

Subtracting 51349999 from its reverse (99994315), we obtain a triangular number (48644316 = T₉₈₆₃).

The spelling of 51349999 in words is "fifty-one million, three hundred forty-nine thousand, nine hundred ninety-nine".