661034772 has 18 divisors (see below), whose sum is σ = 1670949098. Its totient is φ = 220344912.

The previous prime is 661034767. The next prime is 661034827. The reversal of 661034772 is 277430166.

661034772 is a `hidden beast` number, since 6 + 610 + 34 + 7 + 7 + 2 = 666.

661034772 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 601034256 + 60000516 = 24516^2 + 7746^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 18362077 = 661034772 / (6 + 6 + 1 + 0 + 3 + 4 + 7 + 7 + 2).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9181003 + ... + 9181074.

Almost surely, 2^661034772 is an apocalyptic number.

It is an amenable number.

661034772 is an abundant number, since it is smaller than the sum of its proper divisors (1009914326).

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

661034772 is a wasteful number, since it uses less digits than its factorization.

661034772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18362087 (or 18362082 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 36.

The square root of 661034772 is about 25710.5964924970. The cubic root of 661034772 is about 871.1135483531.

The spelling of 661034772 in words is "six hundred sixty-one million, thirty-four thousand, seven hundred seventy-two".