21401193 has 16 divisors (see below), whose sum is σ = 31442112. Its totient is φ = 12840000.

The previous prime is 21401137. The next prime is 21401203. The reversal of 21401193 is 39110412.

It is not a de Polignac number, because 21401193 - 2⁸ = 21400937 is a prime.

It is a super-2 number, since 2×21401193² = 916022123646498, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21401123) 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, 123 + ... + 6543.

It is an arithmetic number, because the mean of its divisors is an integer number (1965132).

Almost surely, 2^21401193 is an apocalyptic number.

It is an amenable number.

21401193 is a deficient number, since it is larger than the sum of its proper divisors (10040919).

21401193 is a wasteful number, since it uses less digits than its factorization.

21401193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6536.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 21401193 is about 4626.1423454105. The cubic root of 21401193 is about 277.6382688911.

It can be divided in two parts, 2140 and 1193, that added together give a palindrome (3333).

The spelling of 21401193 in words is "twenty-one million, four hundred one thousand, one hundred ninety-three".