21025714428 has 96 divisors (see below), whose sum is σ = 55194048000. Its totient is φ = 6921186048.

The previous prime is 21025714421. The next prime is 21025714441. The reversal of 21025714428 is 82441752012.

21025714428 is a `hidden beast` number, since 21 + 0 + 2 + 571 + 44 + 28 = 666.

It is a super-3 number, since 3×21025714428³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21025714392 and 21025714401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21025714421) 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, 3891673 + ... + 3897071.

It is an arithmetic number, because the mean of its divisors is an integer number (574938000).

Almost surely, 2^21025714428 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 21025714428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27597024000).

21025714428 is an abundant number, since it is smaller than the sum of its proper divisors (34168333572).

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

21025714428 is a wasteful number, since it uses less digits than its factorization.

21025714428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5856 (or 5848 counting only the distinct ones).

The product of its (nonzero) digits is 35840, while the sum is 36.

The spelling of 21025714428 in words is "twenty-one billion, twenty-five million, seven hundred fourteen thousand, four hundred twenty-eight".