21320442342 has 48 divisors (see below), whose sum is σ = 48863119968. Its totient is φ = 6704691840.

The previous prime is 21320442337. The next prime is 21320442371. The reversal of 21320442342 is 24324402312.

21320442342 is a `hidden beast` number, since 213 + 2 + 0 + 442 + 3 + 4 + 2 = 666.

It is a super-2 number, since 2×21320442342² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

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, 322509 + ... + 382952.

It is an arithmetic number, because the mean of its divisors is an integer number (1017981666).

Almost surely, 2^21320442342 is an apocalyptic number.

21320442342 is an abundant number, since it is smaller than the sum of its proper divisors (27542677626).

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

21320442342 is a wasteful number, since it uses less digits than its factorization.

21320442342 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705565 (or 705562 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 27.

Adding to 21320442342 its reverse (24324402312), we get a palindrome (45644844654).

The spelling of 21320442342 in words is "twenty-one billion, three hundred twenty million, four hundred forty-two thousand, three hundred forty-two".