21177896064 has 256 divisors, whose sum is σ = 65212076160. Its totient is φ = 6030950400.

The previous prime is 21177896063. The next prime is 21177896087. The reversal of 21177896064 is 46069877112.

It is a super-3 number, since 3×21177896064³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a junction number, because it is equal to n+sod(n) for n = 21177895998 and 21177896016.

It is not an unprimeable number, because it can be changed into a prime (21177896063) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5174659 + ... + 5178749.

Almost surely, 2^21177896064 is an apocalyptic number.

21177896064 is a gapful number since it is divisible by the number (24) 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 21177896064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32606038080).

21177896064 is an abundant number, since it is smaller than the sum of its proper divisors (44034180096).

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

21177896064 is a wasteful number, since it uses less digits than its factorization.

21177896064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4199 (or 4187 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 51.

The spelling of 21177896064 in words is "twenty-one billion, one hundred seventy-seven million, eight hundred ninety-six thousand, sixty-four".