1661715755 has 8 divisors (see below), whose sum is σ = 2278924512. Its totient is φ = 1139462208.

The previous prime is 1661715751. The next prime is 1661715761. The reversal of 1661715755 is 5575171661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1661715755 - 2² = 1661715751 is a prime.

It is a super-2 number, since 2×1661715755² = 5522598500830440050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1661715751) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23738762 + ... + 23738831.

It is an arithmetic number, because the mean of its divisors is an integer number (284865564).

Almost surely, 2^1661715755 is an apocalyptic number.

1661715755 is a deficient number, since it is larger than the sum of its proper divisors (617208757).

1661715755 is an equidigital number, since it uses as much as digits as its factorization.

1661715755 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47477605.

The product of its digits is 220500, while the sum is 44.

The square root of 1661715755 is about 40764.1479121053. The cubic root of 1661715755 is about 1184.4559461388.

The spelling of 1661715755 in words is "one billion, six hundred sixty-one million, seven hundred fifteen thousand, seven hundred fifty-five".