21477317530646 has 4 divisors (see below), whose sum is σ = 32215976295972. Its totient is φ = 10738658765322.

The previous prime is 21477317530619. The next prime is 21477317530703. The reversal of 21477317530646 is 64603571377412.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×21477317530646² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21477317530591 and 21477317530600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5369329382660 + ... + 5369329382663.

It is an arithmetic number, because the mean of its divisors is an integer number (8053994073993).

Almost surely, 2^{21477317530646} is an apocalyptic number.

21477317530646 is a deficient number, since it is larger than the sum of its proper divisors (10738658765326).

21477317530646 is a wasteful number, since it uses less digits than its factorization.

21477317530646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10738658765325.

The product of its (nonzero) digits is 17781120, while the sum is 56.

The spelling of 21477317530646 in words is "twenty-one trillion, four hundred seventy-seven billion, three hundred seventeen million, five hundred thirty thousand, six hundred forty-six".