21474540121 has 4 divisors (see below), whose sum is σ = 21507731712. Its totient is φ = 21441348532.

The previous prime is 21474540103. The next prime is 21474540151. The reversal of 21474540121 is 12104547412.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21474540121 - 2¹¹ = 21474538073 is a prime.

It is a super-2 number, since 2×21474540121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21474540151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16594825 + ... + 16596118.

It is an arithmetic number, because the mean of its divisors is an integer number (5376932928).

Almost surely, 2^21474540121 is an apocalyptic number.

It is an amenable number.

21474540121 is a deficient number, since it is larger than the sum of its proper divisors (33191591).

21474540121 is an equidigital number, since it uses as much as digits as its factorization.

21474540121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33191590.

The product of its (nonzero) digits is 8960, while the sum is 31.

The spelling of 21474540121 in words is "twenty-one billion, four hundred seventy-four million, five hundred forty thousand, one hundred twenty-one".