1661617152 has 440 divisors, whose sum is σ = 5659152576. Its totient is φ = 481738752.

The previous prime is 1661617141. The next prime is 1661617169. The reversal of 1661617152 is 2517161661.

It is a happy number.

1661617152 is a `hidden beast` number, since 16 + 616 + 17 + 15 + 2 = 666.

It is a super-2 number, since 2×1661617152² = 5521943119641182208, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

Its product of digits (15120) is a multiple of the sum of its prime divisors (108).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 24800223 + ... + 24800289.

Almost surely, 2^1661617152 is an apocalyptic number.

1661617152 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 1661617152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2829576288).

1661617152 is an abundant number, since it is smaller than the sum of its proper divisors (3997535424).

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

1661617152 is a wasteful number, since it uses less digits than its factorization.

1661617152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 108 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 1661617152 is about 40762.9384613033. The cubic root of 1661617152 is about 1184.4325179001.

The spelling of 1661617152 in words is "one billion, six hundred sixty-one million, six hundred seventeen thousand, one hundred fifty-two".