21101320401 has 16 divisors (see below), whose sum is σ = 32173131648. Its totient is φ = 12050870400.

The previous prime is 21101320379. The next prime is 21101320403. The reversal of 21101320401 is 10402310112.

It is not a de Polignac number, because 21101320401 - 2⁶ = 21101320337 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21101320403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 255790 + ... + 328071.

It is an arithmetic number, because the mean of its divisors is an integer number (2010820728).

Almost surely, 2^21101320401 is an apocalyptic number.

21101320401 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21101320401 is a deficient number, since it is larger than the sum of its proper divisors (11071811247).

21101320401 is a wasteful number, since it uses less digits than its factorization.

21101320401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 585592.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21101320401 its reverse (10402310112), we get a palindrome (31503630513).

The spelling of 21101320401 in words is "twenty-one billion, one hundred one million, three hundred twenty thousand, four hundred one".