515721372 has 12 divisors (see below), whose sum is σ = 1203349896. Its totient is φ = 171907120.

The previous prime is 515721361. The next prime is 515721377. The reversal of 515721372 is 273127515.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (515721377) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21488379 + ... + 21488402.

It is an arithmetic number, because the mean of its divisors is an integer number (100279158).

Almost surely, 2^515721372 is an apocalyptic number.

It is an amenable number.

515721372 is an abundant number, since it is smaller than the sum of its proper divisors (687628524).

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

515721372 is a wasteful number, since it uses less digits than its factorization.

515721372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42976788 (or 42976786 counting only the distinct ones).

The product of its digits is 14700, while the sum is 33.

The square root of 515721372 is about 22709.4995981858. The cubic root of 515721372 is about 801.9335376088.

Adding to 515721372 its reverse (273127515), we get a palindrome (788848887).

The spelling of 515721372 in words is "five hundred fifteen million, seven hundred twenty-one thousand, three hundred seventy-two".