10661388516 has 27 divisors (see below), whose sum is σ = 26951187081. Its totient is φ = 3553589664.

The previous prime is 10661388511. The next prime is 10661388539. The reversal of 10661388516 is 61588316601.

The square root of 10661388516 is 103254.

It is a perfect power (a square), and thus also a powerful number.

10661388516 is a `hidden beast` number, since 10 + 6 + 613 + 8 + 8 + 5 + 16 = 666.

It can be written as a sum of positive squares in only one way, i.e., 4836646116 + 5824742400 = 69546^2 + 76320^2 .

It is a super-2 number, since 2×10661388516² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (10661388511) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 610920 + ... + 628128.

Almost surely, 2^10661388516 is an apocalyptic number.

10661388516 is the 103254-th square number.

It is an amenable number.

10661388516 is an abundant number, since it is smaller than the sum of its proper divisors (16289798565).

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

10661388516 is an frugal number, since it uses more digits than its factorization.

10661388516 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34428 (or 17214 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The spelling of 10661388516 in words is "ten billion, six hundred sixty-one million, three hundred eighty-eight thousand, five hundred sixteen".