1661952577 has 4 divisors (see below), whose sum is σ = 1662463936. Its totient is φ = 1661441220.

The previous prime is 1661952559. The next prime is 1661952583. The reversal of 1661952577 is 7752591661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1661952577 - 2¹¹ = 1661950529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1661952577.

It is not an unprimeable number, because it can be changed into a prime (1661952557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 250773 + ... + 257314.

It is an arithmetic number, because the mean of its divisors is an integer number (415615984).

Almost surely, 2^1661952577 is an apocalyptic number.

It is an amenable number.

1661952577 is a deficient number, since it is larger than the sum of its proper divisors (511359).

1661952577 is an equidigital number, since it uses as much as digits as its factorization.

1661952577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 511358.

The product of its digits is 793800, while the sum is 49.

The square root of 1661952577 is about 40767.0525915230. The cubic root of 1661952577 is about 1184.5122116585.

It can be divided in two parts, 16619 and 52577, that added together give a palindrome (69196).

The spelling of 1661952577 in words is "one billion, six hundred sixty-one million, nine hundred fifty-two thousand, five hundred seventy-seven".