51123613 has 4 divisors (see below), whose sum is σ = 51886720. Its totient is φ = 50360508.

The previous prime is 51123599. The next prime is 51123643. The reversal of 51123613 is 31632115.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-51123613 is a prime.

It is a super-2 number, since 2×51123613² = 5227247612347538, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51123643) 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, 381453 + ... + 381586.

It is an arithmetic number, because the mean of its divisors is an integer number (12971680).

Almost surely, 2^51123613 is an apocalyptic number.

It is an amenable number.

51123613 is a deficient number, since it is larger than the sum of its proper divisors (763107).

51123613 is an equidigital number, since it uses as much as digits as its factorization.

51123613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 763106.

The product of its digits is 540, while the sum is 22.

The square root of 51123613 is about 7150.0778317442. The cubic root of 51123613 is about 371.1423496485.

Adding to 51123613 its reverse (31632115), we get a palindrome (82755728).

The spelling of 51123613 in words is "fifty-one million, one hundred twenty-three thousand, six hundred thirteen".