10661501556 has 36 divisors (see below), whose sum is σ = 27948053952. Its totient is φ = 3553833528.

The previous prime is 10661501531. The next prime is 10661501561. The reversal of 10661501556 is 65510516601.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×10661501556² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 10661501556.

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, 5483340 + ... + 5485283.

It is an arithmetic number, because the mean of its divisors is an integer number (776334832).

Almost surely, 2^10661501556 is an apocalyptic number.

It is an amenable number.

10661501556 is an abundant number, since it is smaller than the sum of its proper divisors (17286552396).

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

10661501556 is a wasteful number, since it uses less digits than its factorization.

10661501556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10968642 (or 10968628 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The spelling of 10661501556 in words is "ten billion, six hundred sixty-one million, five hundred one thousand, five hundred fifty-six".