161562500 has 96 divisors (see below), whose sum is σ = 393748992. Its totient is φ = 57500000.

The previous prime is 161562493. The next prime is 161562517. The reversal of 161562500 is 5265161.

161562500 = 1831² + 1832² + ... + 1877².

It is a super-2 number, since 2×161562500² = 52204882812500000, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 161562500.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3437477 + ... + 3437523.

It is an arithmetic number, because the mean of its divisors is an integer number (4101552).

Almost surely, 2^161562500 is an apocalyptic number.

161562500 is a gapful number since it is divisible by the number (10) 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 161562500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (196874496).

161562500 is an abundant number, since it is smaller than the sum of its proper divisors (232186492).

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

161562500 is an frugal number, since it uses more digits than its factorization.

161562500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97 (or 65 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 26.

The square root of 161562500 is about 12710.7238188862. The cubic root of 161562500 is about 544.6450006954.

It can be divided in two parts, 16 and 1562500, that multiplied together give a square (25000000 = 5000²).

The spelling of 161562500 in words is "one hundred sixty-one million, five hundred sixty-two thousand, five hundred".