21201361247 has 8 divisors (see below), whose sum is σ = 23130997200. Its totient is φ = 19272098560.

The previous prime is 21201361243. The next prime is 21201361289. The reversal of 21201361247 is 74216310212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21201361247 - 2² = 21201361243 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201361243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32879 + ... + 208527.

It is an arithmetic number, because the mean of its divisors is an integer number (2891374650).

Almost surely, 2^21201361247 is an apocalyptic number.

21201361247 is a deficient number, since it is larger than the sum of its proper divisors (1929635953).

21201361247 is a wasteful number, since it uses less digits than its factorization.

21201361247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186633.

The product of its (nonzero) digits is 4032, while the sum is 29.

Adding to 21201361247 its reverse (74216310212), we get a palindrome (95417671459).

The spelling of 21201361247 in words is "twenty-one billion, two hundred one million, three hundred sixty-one thousand, two hundred forty-seven".