21216053420442 has 48 divisors (see below), whose sum is σ = 46049219124480. Its totient is φ = 7059551044896.

The previous prime is 21216053420423. The next prime is 21216053420461. The reversal of 21216053420442 is 24402435061212.

21216053420442 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 60 + 534 + 20 + 4 + 42 = 666.

It is an interprime number because it is at equal distance from previous prime (21216053420423) and next prime (21216053420461).

It is a junction number, because it is equal to n+sod(n) for n = 21216053420397 and 21216053420406.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23454559 + ... + 24342317.

It is an arithmetic number, because the mean of its divisors is an integer number (959358731760).

Almost surely, 2^{21216053420442} is an apocalyptic number.

21216053420442 is an abundant number, since it is smaller than the sum of its proper divisors (24833165704038).

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

21216053420442 is a wasteful number, since it uses less digits than its factorization.

21216053420442 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 890107 (or 890104 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 36.

Adding to 21216053420442 its reverse (24402435061212), we get a palindrome (45618488481654).

The spelling of 21216053420442 in words is "twenty-one trillion, two hundred sixteen billion, fifty-three million, four hundred twenty thousand, four hundred forty-two".