161540700 has 72 divisors (see below), whose sum is σ = 468803328. Its totient is φ = 42947520.

The previous prime is 161540699. The next prime is 161540711. The reversal of 161540700 is 7045161.

It is a congruent number.

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 23 ways as a sum of consecutive naturals, for example, 138319 + ... + 139481.

Almost surely, 2^161540700 is an apocalyptic number.

161540700 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 161540700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (234401664).

161540700 is an abundant number, since it is smaller than the sum of its proper divisors (307262628).

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

161540700 is a wasteful number, since it uses less digits than its factorization.

161540700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1643 (or 1636 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 161540700 is about 12709.8662463458. The cubic root of 161540700 is about 544.6205028590.

Adding to 161540700 its reverse (7045161), we get a palindrome (168585861).

The spelling of 161540700 in words is "one hundred sixty-one million, five hundred forty thousand, seven hundred".