1661306355 has 20 divisors (see below), whose sum is σ = 2978046192. Its totient is φ = 886029840.

The previous prime is 1661306341. The next prime is 1661306369. The reversal of 1661306355 is 5536031661.

1661306355 is a `hidden beast` number, since 1 + 6 + 6 + 13 + 0 + 635 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (1661306341) and next prime (1661306369).

It is not a de Polignac number, because 1661306355 - 2¹⁵ = 1661273587 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2050591 + ... + 2051400.

Almost surely, 2^1661306355 is an apocalyptic number.

1661306355 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1661306355 is a deficient number, since it is larger than the sum of its proper divisors (1316739837).

1661306355 is an equidigital number, since it uses as much as digits as its factorization.

1661306355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4102008 (or 4101999 counting only the distinct ones).

The product of its (nonzero) digits is 48600, while the sum is 36.

The square root of 1661306355 is about 40759.1260333192. The cubic root of 1661306355 is about 1184.3586659448.

It can be divided in two parts, 1661306 and 355, that added together give a palindrome (1661661).

The spelling of 1661306355 in words is "one billion, six hundred sixty-one million, three hundred six thousand, three hundred fifty-five".