1661552061 has 24 divisors (see below), whose sum is σ = 2403601056. Its totient is φ = 1020502080.

The previous prime is 1661552047. The next prime is 1661552063. The reversal of 1661552061 is 1602551661.

It is not a de Polignac number, because 1661552061 - 2¹⁰ = 1661551037 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661552063) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 282531 + ... + 288351.

It is an arithmetic number, because the mean of its divisors is an integer number (100150044).

Almost surely, 2^1661552061 is an apocalyptic number.

It is an amenable number.

1661552061 is a deficient number, since it is larger than the sum of its proper divisors (742048995).

1661552061 is a wasteful number, since it uses less digits than its factorization.

1661552061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6413 (or 6400 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 33.

The square root of 1661552061 is about 40762.1400444089. The cubic root of 1661552061 is about 1184.4170516612.

The spelling of 1661552061 in words is "one billion, six hundred sixty-one million, five hundred fifty-two thousand, sixty-one".