21876251977 has 8 divisors (see below), whose sum is σ = 23030249760. Its totient is φ = 20722515840.

The previous prime is 21876251959. The next prime is 21876251981. The reversal of 21876251977 is 77915267812.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21876251977 is a prime.

It is a super-2 number, since 2×21876251977² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21876251377) 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, 119673 + ... + 240985.

It is an arithmetic number, because the mean of its divisors is an integer number (2878781220).

Almost surely, 2^21876251977 is an apocalyptic number.

It is an amenable number.

21876251977 is a deficient number, since it is larger than the sum of its proper divisors (1153997783).

21876251977 is a wasteful number, since it uses less digits than its factorization.

21876251977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130823.

The product of its digits is 2963520, while the sum is 55.

The spelling of 21876251977 in words is "twenty-one billion, eight hundred seventy-six million, two hundred fifty-one thousand, nine hundred seventy-seven".