16381211520 has 64 divisors (see below), whose sum is σ = 52215117840. Its totient is φ = 4368322560.

The previous prime is 16381211503. The next prime is 16381211521. The reversal of 16381211520 is 2511218361.

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16381211521) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4264021 + ... + 4267860.

Almost surely, 2^16381211520 is an apocalyptic number.

16381211520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16381211520 is an abundant number, since it is smaller than the sum of its proper divisors (35833906320).

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

16381211520 is an equidigital number, since it uses as much as digits as its factorization.

16381211520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8531903 (or 8531891 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 30.

Adding to 16381211520 its reverse (2511218361), we get a palindrome (18892429881).

The spelling of 16381211520 in words is "sixteen billion, three hundred eighty-one million, two hundred eleven thousand, five hundred twenty".