21451401 has 12 divisors (see below), whose sum is σ = 31150080. Its totient is φ = 14224920.

The previous prime is 21451373. The next prime is 21451427. The reversal of 21451401 is 10415412.

21451401 is a `hidden beast` number, since 214 + 51 + 401 = 666.

It is not a de Polignac number, because 21451401 - 2⁵ = 21451369 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21451471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4521 + ... + 7958.

It is an arithmetic number, because the mean of its divisors is an integer number (2595840).

Almost surely, 2^21451401 is an apocalyptic number.

It is an amenable number.

21451401 is a deficient number, since it is larger than the sum of its proper divisors (9698679).

21451401 is a wasteful number, since it uses less digits than its factorization.

21451401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12676 (or 12673 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 21451401 is about 4631.5657179835. The cubic root of 21451401 is about 277.8552159152.

Adding to 21451401 its reverse (10415412), we get a palindrome (31866813).

It can be divided in two parts, 214 and 51401, that added together give a palindrome (51615).

The spelling of 21451401 in words is "twenty-one million, four hundred fifty-one thousand, four hundred one".