21234451205401 has 20 divisors (see below), whose sum is σ = 24772579282304. Its totient is φ = 18200571064200.

The previous prime is 21234451205393. The next prime is 21234451205453. The reversal of 21234451205401 is 10450215443212.

It is not a de Polignac number, because 21234451205401 - 2³ = 21234451205393 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21234451205101) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 222743536 + ... + 222838846.

Almost surely, 2^{21234451205401} is an apocalyptic number.

It is an amenable number.

21234451205401 is a deficient number, since it is larger than the sum of its proper divisors (3538128076903).

21234451205401 is an frugal number, since it uses more digits than its factorization.

21234451205401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188130 (or 188109 counting only the distinct ones).

The product of its (nonzero) digits is 38400, while the sum is 34.

Adding to 21234451205401 its reverse (10450215443212), we get a palindrome (31684666648613).

The spelling of 21234451205401 in words is "twenty-one trillion, two hundred thirty-four billion, four hundred fifty-one million, two hundred five thousand, four hundred one".