51619381 has 4 divisors (see below), whose sum is σ = 56312064. Its totient is φ = 46926700.

The previous prime is 51619367. The next prime is 51619387. The reversal of 51619381 is 18391615.

51619381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 51619381 - 2⁵ = 51619349 is a prime.

It is a super-2 number, since 2×51619381² = 5329120989646322, 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 (51619387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2346325 + ... + 2346346.

It is an arithmetic number, because the mean of its divisors is an integer number (14078016).

Almost surely, 2^51619381 is an apocalyptic number.

It is an amenable number.

51619381 is a deficient number, since it is larger than the sum of its proper divisors (4692683).

51619381 is a wasteful number, since it uses less digits than its factorization.

51619381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4692682.

The product of its digits is 6480, while the sum is 34.

The square root of 51619381 is about 7184.6629009300. The cubic root of 51619381 is about 372.3382021824.

The spelling of 51619381 in words is "fifty-one million, six hundred nineteen thousand, three hundred eighty-one".