21340647461 has 8 divisors (see below), whose sum is σ = 24956505024. Its totient is φ = 17866588320.

The previous prime is 21340647457. The next prime is 21340647469. The reversal of 21340647461 is 16474604312.

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

It is not a de Polignac number, because 21340647461 - 2² = 21340647457 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 (21340647469) 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, 35449280 + ... + 35449881.

It is an arithmetic number, because the mean of its divisors is an integer number (3119563128).

Almost surely, 2^21340647461 is an apocalyptic number.

It is an amenable number.

21340647461 is a deficient number, since it is larger than the sum of its proper divisors (3615857563).

21340647461 is an equidigital number, since it uses as much as digits as its factorization.

21340647461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70899211.

The product of its (nonzero) digits is 96768, while the sum is 38.

The spelling of 21340647461 in words is "twenty-one billion, three hundred forty million, six hundred forty-seven thousand, four hundred sixty-one".