21275292377 has 4 divisors (see below), whose sum is σ = 21282456336. Its totient is φ = 21268128420.

The previous prime is 21275292373. The next prime is 21275292391. The reversal of 21275292377 is 77329257212.

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 not a de Polignac number, because 21275292377 - 2² = 21275292373 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21275292373) 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, 3577523 + ... + 3583464.

It is an arithmetic number, because the mean of its divisors is an integer number (5320614084).

Almost surely, 2^21275292377 is an apocalyptic number.

It is an amenable number.

21275292377 is a deficient number, since it is larger than the sum of its proper divisors (7163959).

21275292377 is an equidigital number, since it uses as much as digits as its factorization.

21275292377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7163958.

The product of its digits is 740880, while the sum is 47.

The spelling of 21275292377 in words is "twenty-one billion, two hundred seventy-five million, two hundred ninety-two thousand, three hundred seventy-seven".