21270690289728 has 392 divisors, whose sum is σ = 70903681570560. Its totient is φ = 6271450997760.

The previous prime is 21270690289727. The next prime is 21270690289843. The reversal of 21270690289728 is 82798209607212.

21270690289728 is a `hidden beast` number, since 2 + 1 + 270 + 69 + 0 + 289 + 7 + 28 = 666.

It is not an unprimeable number, because it can be changed into a prime (21270690289727) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 18428913 + ... + 19549071.

Almost surely, 2^{21270690289728} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21270690289728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35451840785280).

21270690289728 is an abundant number, since it is smaller than the sum of its proper divisors (49632991280832).

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

21270690289728 is a wasteful number, since it uses less digits than its factorization.

21270690289728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1120237 (or 1120212 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 63.

The spelling of 21270690289728 in words is "twenty-one trillion, two hundred seventy billion, six hundred ninety million, two hundred eighty-nine thousand, seven hundred twenty-eight".