1661607111020 has 24 divisors (see below), whose sum is σ = 3496944095568. Its totient is φ = 663201099200.

The previous prime is 1661607111019. The next prime is 1661607111023. The reversal of 1661607111020 is 201117061661.

It is not an unprimeable number, because it can be changed into a prime (1661607111023) 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 7 ways as a sum of consecutive naturals, for example, 90099626 + ... + 90118065.

It is an arithmetic number, because the mean of its divisors is an integer number (145706003982).

Almost surely, 2^{1661607111020} is an apocalyptic number.

1661607111020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1661607111020 is an abundant number, since it is smaller than the sum of its proper divisors (1835336984548).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1661607111020 is a wasteful number, since it uses less digits than its factorization.

1661607111020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180218161 (or 180218159 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 32.

The spelling of 1661607111020 in words is "one trillion, six hundred sixty-one billion, six hundred seven million, one hundred eleven thousand, twenty".