161007820 has 48 divisors (see below), whose sum is σ = 361464768. Its totient is φ = 60093440.

The previous prime is 161007817. The next prime is 161007823. The reversal of 161007820 is 28700161.

It is an interprime number because it is at equal distance from previous prime (161007817) and next prime (161007823).

It is not an unprimeable number, because it can be changed into a prime (161007823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14592 + ... + 23128.

It is an arithmetic number, because the mean of its divisors is an integer number (7530516).

Almost surely, 2^161007820 is an apocalyptic number.

161007820 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 161007820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180732384).

161007820 is an abundant number, since it is smaller than the sum of its proper divisors (200456948).

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

161007820 is a wasteful number, since it uses less digits than its factorization.

161007820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8610 (or 8608 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 25.

The square root of 161007820 is about 12688.8856878766. The cubic root of 161007820 is about 544.0209902152.

Adding to 161007820 its reverse (28700161), we get a palindrome (189707981).

The spelling of 161007820 in words is "one hundred sixty-one million, seven thousand, eight hundred twenty".