21887827657 has 8 divisors (see below), whose sum is σ = 21959697312. Its totient is φ = 21816076800.

The previous prime is 21887827649. The next prime is 21887827697. The reversal of 21887827657 is 75672878812.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21887827657 - 2³ = 21887827649 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21887827595 and 21887827604.

It is not an unprimeable number, because it can be changed into a prime (21887827627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 347182 + ... + 405352.

It is an arithmetic number, because the mean of its divisors is an integer number (2744962164).

Almost surely, 2^21887827657 is an apocalyptic number.

It is an amenable number.

21887827657 is a deficient number, since it is larger than the sum of its proper divisors (71869655).

21887827657 is an equidigital number, since it uses as much as digits as its factorization.

21887827657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59399.

The product of its digits is 21073920, while the sum is 61.

The spelling of 21887827657 in words is "twenty-one billion, eight hundred eighty-seven million, eight hundred twenty-seven thousand, six hundred fifty-seven".