1661166528 has 56 divisors (see below), whose sum is σ = 5023055232. Its totient is φ = 474618624.

The previous prime is 1661166517. The next prime is 1661166571. The reversal of 1661166528 is 8256611661.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a self number, because there is not a number n which added to its sum of digits gives 1661166528.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 616650 + ... + 619337.

Almost surely, 2^1661166528 is an apocalyptic number.

It is an amenable number.

1661166528 is an abundant number, since it is smaller than the sum of its proper divisors (3361888704).

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

1661166528 is a wasteful number, since it uses less digits than its factorization.

1661166528 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1236009 (or 1235999 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The square root of 1661166528 is about 40757.4107126545. The cubic root of 1661166528 is about 1184.3254370814.

The spelling of 1661166528 in words is "one billion, six hundred sixty-one million, one hundred sixty-six thousand, five hundred twenty-eight".