1661985024 has 288 divisors, whose sum is σ = 5439329280. Its totient is φ = 439934976.

The previous prime is 1661985023. The next prime is 1661985047. The reversal of 1661985024 is 4205891661.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661985023) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5413479 + ... + 5413785.

It is an arithmetic number, because the mean of its divisors is an integer number (18886560).

Almost surely, 2^1661985024 is an apocalyptic number.

1661985024 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1661985024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2719664640).

1661985024 is an abundant number, since it is smaller than the sum of its proper divisors (3777344256).

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

1661985024 is a wasteful number, since it uses less digits than its factorization.

1661985024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405 (or 391 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 42.

The square root of 1661985024 is about 40767.4505457479. The cubic root of 1661985024 is about 1184.5199201852.

The spelling of 1661985024 in words is "one billion, six hundred sixty-one million, nine hundred eighty-five thousand, twenty-four".