21016254462840 has 1536 divisors, whose sum is σ = 93875169024000. Its totient is φ = 4102455361536.

The previous prime is 21016254462821. The next prime is 21016254462923. The reversal of 21016254462840 is 4826445261012.

21016254462840 is a `hidden beast` number, since 2 + 1 + 0 + 1 + 6 + 2 + 544 + 62 + 8 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 887161716 + ... + 887185404.

It is an arithmetic number, because the mean of its divisors is an integer number (61116646500).

Almost surely, 2^{21016254462840} is an apocalyptic number.

21016254462840 is a gapful number since it is divisible by the number (20) 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 21016254462840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46937584512000).

21016254462840 is an abundant number, since it is smaller than the sum of its proper divisors (72858914561160).

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

21016254462840 is a wasteful number, since it uses less digits than its factorization.

21016254462840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23811 (or 23795 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 45.

The spelling of 21016254462840 in words is "twenty-one trillion, sixteen billion, two hundred fifty-four million, four hundred sixty-two thousand, eight hundred forty".