51661325 has 12 divisors (see below), whose sum is σ = 66269940. Its totient is φ = 39903360.

The previous prime is 51661307. The next prime is 51661333. The reversal of 51661325 is 52316615.

It can be written as a sum of positive squares in 6 ways, for example, as 137641 + 51523684 = 371^2 + 7178^2 .

It is not a de Polignac number, because 51661325 - 2⁶ = 51661261 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34904 + ... + 36353.

It is an arithmetic number, because the mean of its divisors is an integer number (5522495).

Almost surely, 2^51661325 is an apocalyptic number.

It is an amenable number.

51661325 is a deficient number, since it is larger than the sum of its proper divisors (14608615).

51661325 is a wasteful number, since it uses less digits than its factorization.

51661325 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71296 (or 71291 counting only the distinct ones).

The product of its digits is 5400, while the sum is 29.

The square root of 51661325 is about 7187.5813038880. The cubic root of 51661325 is about 372.4390242970.

The spelling of 51661325 in words is "fifty-one million, six hundred sixty-one thousand, three hundred twenty-five".