51323561 has 8 divisors (see below), whose sum is σ = 54872064. Its totient is φ = 47833920.

The previous prime is 51323543. The next prime is 51323563. The reversal of 51323561 is 16532315.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-51323561 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 51323561.

It is not an unprimeable number, because it can be changed into a prime (51323563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12905 + ... + 16406.

It is an arithmetic number, because the mean of its divisors is an integer number (6859008).

Almost surely, 2^51323561 is an apocalyptic number.

It is an amenable number.

51323561 is a deficient number, since it is larger than the sum of its proper divisors (3548503).

51323561 is a wasteful number, since it uses less digits than its factorization.

51323561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29431.

The product of its digits is 2700, while the sum is 26.

The square root of 51323561 is about 7164.0464124683. The cubic root of 51323561 is about 371.6255747188.

Adding to 51323561 its reverse (16532315), we get a palindrome (67855876).

The spelling of 51323561 in words is "fifty-one million, three hundred twenty-three thousand, five hundred sixty-one".