161321020700 has 72 divisors (see below), whose sum is σ = 400130640000. Its totient is φ = 55302528960.

The previous prime is 161321020699. The next prime is 161321020739. The reversal of 161321020700 is 7020123161.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8179451 + ... + 8199149.

It is an arithmetic number, because the mean of its divisors is an integer number (5557370000).

Almost surely, 2^161321020700 is an apocalyptic number.

161321020700 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

161321020700 is an abundant number, since it is smaller than the sum of its proper divisors (238809619300).

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

161321020700 is a wasteful number, since it uses less digits than its factorization.

161321020700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31419 (or 31412 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 23.

Adding to 161321020700 its reverse (7020123161), we get a palindrome (168341143861).

The spelling of 161321020700 in words is "one hundred sixty-one billion, three hundred twenty-one million, twenty thousand, seven hundred".