21310655377 has 4 divisors (see below), whose sum is σ = 23247987696. Its totient is φ = 19373323060.

The previous prime is 21310655357. The next prime is 21310655389. The reversal of 21310655377 is 77355601312.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21310655377 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21310655357) 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 3 ways as a sum of consecutive naturals, for example, 968666143 + ... + 968666164.

It is an arithmetic number, because the mean of its divisors is an integer number (5811996924).

Almost surely, 2^21310655377 is an apocalyptic number.

It is an amenable number.

21310655377 is a deficient number, since it is larger than the sum of its proper divisors (1937332319).

21310655377 is a wasteful number, since it uses less digits than its factorization.

21310655377 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1937332318.

The product of its (nonzero) digits is 132300, while the sum is 40.

The spelling of 21310655377 in words is "twenty-one billion, three hundred ten million, six hundred fifty-five thousand, three hundred seventy-seven".