51840613 has 4 divisors (see below), whose sum is σ = 56553408. Its totient is φ = 47127820.

The previous prime is 51840601. The next prime is 51840617. The reversal of 51840613 is 31604815.

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 51840613 - 2⁹ = 51840101 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 (51840617) 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, 2356381 + ... + 2356402.

It is an arithmetic number, because the mean of its divisors is an integer number (14138352).

Almost surely, 2^51840613 is an apocalyptic number.

It is an amenable number.

51840613 is a deficient number, since it is larger than the sum of its proper divisors (4712795).

51840613 is a wasteful number, since it uses less digits than its factorization.

51840613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4712794.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 51840613 is about 7200.0425693186. The cubic root of 51840613 is about 372.8693704105.

The spelling of 51840613 in words is "fifty-one million, eight hundred forty thousand, six hundred thirteen".