21277788533 has 8 divisors (see below), whose sum is σ = 22522802400. Its totient is φ = 20045287728.

The previous prime is 21277788529. The next prime is 21277788541. The reversal of 21277788533 is 33588777212.

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 21277788533 - 2² = 21277788529 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 (21277788593) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3124766 + ... + 3131567.

It is an arithmetic number, because the mean of its divisors is an integer number (2815350300).

Almost surely, 2^21277788533 is an apocalyptic number.

It is an amenable number.

21277788533 is a deficient number, since it is larger than the sum of its proper divisors (1245013867).

21277788533 is a wasteful number, since it uses less digits than its factorization.

21277788533 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6256531.

The product of its digits is 3951360, while the sum is 53.

The spelling of 21277788533 in words is "twenty-one billion, two hundred seventy-seven million, seven hundred eighty-eight thousand, five hundred thirty-three".