161780351020 has 48 divisors (see below), whose sum is σ = 348080283936. Its totient is φ = 63123776000.

The previous prime is 161780351011. The next prime is 161780351027. The reversal of 161780351020 is 20153087161.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (161780351027) 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, 7156335 + ... + 7178905.

It is an arithmetic number, because the mean of its divisors is an integer number (7251672582).

Almost surely, 2^161780351020 is an apocalyptic number.

161780351020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161780351020 is an abundant number, since it is smaller than the sum of its proper divisors (186299932916).

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

161780351020 is a wasteful number, since it uses less digits than its factorization.

161780351020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31362 (or 31360 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 34.

The spelling of 161780351020 in words is "one hundred sixty-one billion, seven hundred eighty million, three hundred fifty-one thousand, twenty".