1661893632 has 352 divisors, whose sum is σ = 5827235840. Its totient is φ = 457850880.

The previous prime is 1661893619. The next prime is 1661893637. The reversal of 1661893632 is 2363981661.

1661893632 is a `hidden beast` number, since 1 + 6 + 6 + 1 + 8 + 9 + 3 + 632 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661893637) 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, 5999478 + ... + 5999754.

Almost surely, 2^1661893632 is an apocalyptic number.

1661893632 is a gapful number since it is divisible by the number (12) 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 1661893632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2913617920).

1661893632 is an abundant number, since it is smaller than the sum of its proper divisors (4165342208).

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

1661893632 is a wasteful number, since it uses less digits than its factorization.

1661893632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344 (or 320 counting only the distinct ones).

The product of its digits is 279936, while the sum is 45.

The square root of 1661893632 is about 40766.3296361102. The cubic root of 1661893632 is about 1184.4982076693.

The spelling of 1661893632 in words is "one billion, six hundred sixty-one million, eight hundred ninety-three thousand, six hundred thirty-two".