51531340 has 36 divisors (see below), whose sum is σ = 125886096. Its totient is φ = 17667552.

The previous prime is 51531323. The next prime is 51531341. The reversal of 51531340 is 4313515.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (51531341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25312 + ... + 27271.

It is an arithmetic number, because the mean of its divisors is an integer number (3496836).

Almost surely, 2^51531340 is an apocalyptic number.

It is an amenable number.

51531340 is an abundant number, since it is smaller than the sum of its proper divisors (74354756).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51531340 is a wasteful number, since it uses less digits than its factorization.

51531340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52606 (or 52597 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 51531340 is about 7178.5332763734. The cubic root of 51531340 is about 372.1263974843.

Adding to 51531340 its reverse (4313515), we get a palindrome (55844855).

The spelling of 51531340 in words is "fifty-one million, five hundred thirty-one thousand, three hundred forty".