21367633749487 has 4 divisors (see below), whose sum is σ = 21945137364376. Its totient is φ = 20790130134600.

The previous prime is 21367633749467. The next prime is 21367633749541. The reversal of 21367633749487 is 78494733676312.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21367633749487 - 2³¹ = 21365486265839 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 (21367633749437) 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, 288751807389 + ... + 288751807462.

It is an arithmetic number, because the mean of its divisors is an integer number (5486284341094).

Almost surely, 2^{21367633749487} is an apocalyptic number.

21367633749487 is a deficient number, since it is larger than the sum of its proper divisors (577503614889).

21367633749487 is an equidigital number, since it uses as much as digits as its factorization.

21367633749487 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577503614888.

The product of its digits is 768144384, while the sum is 70.

The spelling of 21367633749487 in words is "twenty-one trillion, three hundred sixty-seven billion, six hundred thirty-three million, seven hundred forty-nine thousand, four hundred eighty-seven".