21377131776 has 1296 divisors, whose sum is σ = 89628844032. Its totient is φ = 4744396800.

The previous prime is 21377131709. The next prime is 21377131829. The reversal of 21377131776 is 67713177312.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 689584881 + ... + 689584911.

Almost surely, 2^21377131776 is an apocalyptic number.

21377131776 is a gapful number since it is divisible by the number (26) 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 21377131776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44814422016).

21377131776 is an abundant number, since it is smaller than the sum of its proper divisors (68251712256).

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

21377131776 is a wasteful number, since it uses less digits than its factorization.

21377131776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120 (or 90 counting only the distinct ones).

The product of its digits is 259308, while the sum is 45.

The spelling of 21377131776 in words is "twenty-one billion, three hundred seventy-seven million, one hundred thirty-one thousand, seven hundred seventy-six".