51540212 has 6 divisors (see below), whose sum is σ = 90195378. Its totient is φ = 25770104.

The previous prime is 51540211. The next prime is 51540233. The reversal of 51540212 is 21204515.

It can be written as a sum of positive squares in only one way, i.e., 46185616 + 5354596 = 6796^2 + 2314^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51540211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6442523 + ... + 6442530.

It is an arithmetic number, because the mean of its divisors is an integer number (15032563).

Almost surely, 2^51540212 is an apocalyptic number.

It is an amenable number.

51540212 is a deficient number, since it is larger than the sum of its proper divisors (38655166).

51540212 is a wasteful number, since it uses less digits than its factorization.

51540212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12885057 (or 12885055 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 51540212 is about 7179.1512033109. The cubic root of 51540212 is about 372.1477522298.

Adding to 51540212 its reverse (21204515), we get a palindrome (72744727).

The spelling of 51540212 in words is "fifty-one million, five hundred forty thousand, two hundred twelve".