1661023512 has 48 divisors (see below), whose sum is σ = 4501074240. Its totient is φ = 553370688.

The previous prime is 1661023501. The next prime is 1661023513. The reversal of 1661023512 is 2153201661.

1661023512 is a `hidden beast` number, since 1 + 6 + 610 + 2 + 35 + 12 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661023513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 153678 + ... + 164130.

It is an arithmetic number, because the mean of its divisors is an integer number (93772380).

Almost surely, 2^1661023512 is an apocalyptic number.

1661023512 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1661023512 is an abundant number, since it is smaller than the sum of its proper divisors (2840050728).

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

1661023512 is a wasteful number, since it uses less digits than its factorization.

1661023512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12672 (or 12665 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 1661023512 is about 40755.6561964103. The cubic root of 1661023512 is about 1184.2914484466.

The spelling of 1661023512 in words is "one billion, six hundred sixty-one million, twenty-three thousand, five hundred twelve".