21031201201009 has 4 divisors (see below), whose sum is σ = 21031210449216. Its totient is φ = 21031191952804.

The previous prime is 21031201200967. The next prime is 21031201201081. The reversal of 21031201201009 is 90010210213012.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 21031201201009 - 2²¹ = 21031199103857 is a prime.

It is a super-2 number, since 2×21031201201009² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21031201201099) 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, 1423212 + ... + 6639874.

It is an arithmetic number, because the mean of its divisors is an integer number (5257802612304).

Almost surely, 2^{21031201201009} is an apocalyptic number.

It is an amenable number.

21031201201009 is a deficient number, since it is larger than the sum of its proper divisors (9248207).

21031201201009 is an equidigital number, since it uses as much as digits as its factorization.

21031201201009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9248206.

The product of its (nonzero) digits is 216, while the sum is 22.

The spelling of 21031201201009 in words is "twenty-one trillion, thirty-one billion, two hundred one million, two hundred one thousand, nine".