21951490271 has 16 divisors (see below), whose sum is σ = 22344189120. Its totient is φ = 21563020800.

The previous prime is 21951490217. The next prime is 21951490273. The reversal of 21951490271 is 17209415912.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21951490271 - 2⁶ = 21951490207 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 (21951490273) 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, 7560206 + ... + 7563108.

It is an arithmetic number, because the mean of its divisors is an integer number (1396511820).

Almost surely, 2^21951490271 is an apocalyptic number.

21951490271 is a deficient number, since it is larger than the sum of its proper divisors (392698849).

21951490271 is a wasteful number, since it uses less digits than its factorization.

21951490271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3586.

The product of its (nonzero) digits is 45360, while the sum is 41.

The spelling of 21951490271 in words is "twenty-one billion, nine hundred fifty-one million, four hundred ninety thousand, two hundred seventy-one".