51323515 has 4 divisors (see below), whose sum is σ = 61588224. Its totient is φ = 41058808.

The previous prime is 51323501. The next prime is 51323521. The reversal of 51323515 is 51532315.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51532315 = 5 ⋅10306463.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-51323515 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 51323515.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5132347 + ... + 5132356.

It is an arithmetic number, because the mean of its divisors is an integer number (15397056).

Almost surely, 2^51323515 is an apocalyptic number.

51323515 is a deficient number, since it is larger than the sum of its proper divisors (10264709).

51323515 is a wasteful number, since it uses less digits than its factorization.

51323515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10264708.

The product of its digits is 2250, while the sum is 25.

The square root of 51323515 is about 7164.0432019915. The cubic root of 51323515 is about 371.6254636926.

The spelling of 51323515 in words is "fifty-one million, three hundred twenty-three thousand, five hundred fifteen".