21357205012534 has 16 divisors (see below), whose sum is σ = 32781465934272. Its totient is φ = 10430059392648.

The previous prime is 21357205012529. The next prime is 21357205012607. The reversal of 21357205012534 is 43521050275312.

It is a super-2 number, since 2×21357205012534² (a number of 27 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 7 ways as a sum of consecutive naturals, for example, 2058097 + ... + 6852019.

It is an arithmetic number, because the mean of its divisors is an integer number (2048841620892).

Almost surely, 2^{21357205012534} is an apocalyptic number.

21357205012534 is a deficient number, since it is larger than the sum of its proper divisors (11424260921738).

21357205012534 is a wasteful number, since it uses less digits than its factorization.

21357205012534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4845771.

The product of its (nonzero) digits is 252000, while the sum is 40.

Adding to 21357205012534 its reverse (43521050275312), we get a palindrome (64878255287846).

The spelling of 21357205012534 in words is "twenty-one trillion, three hundred fifty-seven billion, two hundred five million, twelve thousand, five hundred thirty-four".