161989231950 has 1152 divisors, whose sum is σ = 614990638080. Its totient is φ = 29561241600.

The previous prime is 161989231903. The next prime is 161989231973. The reversal of 161989231950 is 59132989161.

161989231950 is a `hidden beast` number, since 1 + 6 + 198 + 92 + 319 + 50 = 666.

It is a super-2 number, since 2×161989231950² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 489393285 + ... + 489393615.

It is an arithmetic number, because the mean of its divisors is an integer number (533846040).

Almost surely, 2^161989231950 is an apocalyptic number.

161989231950 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 161989231950, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (307495319040).

161989231950 is an abundant number, since it is smaller than the sum of its proper divisors (453001406130).

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

161989231950 is a wasteful number, since it uses less digits than its factorization.

161989231950 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 442 (or 434 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 54.

The spelling of 161989231950 in words is "one hundred sixty-one billion, nine hundred eighty-nine million, two hundred thirty-one thousand, nine hundred fifty".