21477656006 has 4 divisors (see below), whose sum is σ = 32216484012. Its totient is φ = 10738828002.

The previous prime is 21477655951. The next prime is 21477656009. The reversal of 21477656006 is 60065677412.

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

It is a super-2 number, since 2×21477656006² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21477656009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5369414000 + ... + 5369414003.

It is an arithmetic number, because the mean of its divisors is an integer number (8054121003).

Almost surely, 2^21477656006 is an apocalyptic number.

21477656006 is a deficient number, since it is larger than the sum of its proper divisors (10738828006).

21477656006 is a wasteful number, since it uses less digits than its factorization.

21477656006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10738828005.

The product of its (nonzero) digits is 423360, while the sum is 44.

The spelling of 21477656006 in words is "twenty-one billion, four hundred seventy-seven million, six hundred fifty-six thousand, six".