21166390461 has 8 divisors (see below), whose sum is σ = 28267596864. Its totient is φ = 14088055520.

The previous prime is 21166390433. The next prime is 21166390489. The reversal of 21166390461 is 16409366112.

It is an interprime number because it is at equal distance from previous prime (21166390433) and next prime (21166390489).

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 21166390461 - 2⁹ = 21166389949 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21166390561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5715705 + ... + 5719406.

It is an arithmetic number, because the mean of its divisors is an integer number (3533449608).

Almost surely, 2^21166390461 is an apocalyptic number.

It is an amenable number.

21166390461 is a deficient number, since it is larger than the sum of its proper divisors (7101206403).

21166390461 is a wasteful number, since it uses less digits than its factorization.

21166390461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11435731.

The product of its (nonzero) digits is 46656, while the sum is 39.

The spelling of 21166390461 in words is "twenty-one billion, one hundred sixty-six million, three hundred ninety thousand, four hundred sixty-one".