21550899471 has 8 divisors (see below), whose sum is σ = 28781873664. Its totient is φ = 14343595800.

The previous prime is 21550899443. The next prime is 21550899509. The reversal of 21550899471 is 17499805512.

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

It is not a de Polignac number, because 21550899471 - 2¹⁸ = 21550637327 is a prime.

It is a super-3 number, since 3×21550899471³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21550899431) 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, 5915505 + ... + 5919146.

It is an arithmetic number, because the mean of its divisors is an integer number (3597734208).

Almost surely, 2^21550899471 is an apocalyptic number.

21550899471 is a deficient number, since it is larger than the sum of its proper divisors (7230974193).

21550899471 is a wasteful number, since it uses less digits than its factorization.

21550899471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11835261.

The product of its (nonzero) digits is 907200, while the sum is 51.

The spelling of 21550899471 in words is "twenty-one billion, five hundred fifty million, eight hundred ninety-nine thousand, four hundred seventy-one".