21550210071 has 16 divisors (see below), whose sum is σ = 30947266560. Its totient is φ = 13260221280.

The previous prime is 21550210063. The next prime is 21550210081. The reversal of 21550210071 is 17001205512.

It is not a de Polignac number, because 21550210071 - 2³ = 21550210063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21550210081) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 415386 + ... + 464376.

It is an arithmetic number, because the mean of its divisors is an integer number (1934204160).

Almost surely, 2^21550210071 is an apocalyptic number.

21550210071 is a deficient number, since it is larger than the sum of its proper divisors (9397056489).

21550210071 is a wasteful number, since it uses less digits than its factorization.

21550210071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60286.

The product of its (nonzero) digits is 700, while the sum is 24.

Adding to 21550210071 its reverse (17001205512), we get a palindrome (38551415583).

The spelling of 21550210071 in words is "twenty-one billion, five hundred fifty million, two hundred ten thousand, seventy-one".