1505610661 has 16 divisors (see below), whose sum is σ = 1652797440. Its totient is φ = 1365154560.

The previous prime is 1505610649. The next prime is 1505610709. The reversal of 1505610661 is 1660165051.

It is a cyclic number.

It is not a de Polignac number, because 1505610661 - 2¹⁵ = 1505577893 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1505610461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 236956 + ... + 243226.

It is an arithmetic number, because the mean of its divisors is an integer number (103299840).

Almost surely, 2^1505610661 is an apocalyptic number.

It is an amenable number.

1505610661 is a deficient number, since it is larger than the sum of its proper divisors (147186779).

1505610661 is a wasteful number, since it uses less digits than its factorization.

1505610661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6804.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 1505610661 is about 38802.1991773662. The cubic root of 1505610661 is about 1146.1397119681.

The spelling of 1505610661 in words is "one billion, five hundred five million, six hundred ten thousand, six hundred sixty-one".