21707663770 has 128 divisors (see below), whose sum is σ = 44786649600. Its totient is φ = 7517518848.

The previous prime is 21707663693. The next prime is 21707663771. The reversal of 21707663770 is 7736670712.

It is a super-2 number, since 2×21707663770² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21707663770.

It is not an unprimeable number, because it can be changed into a prime (21707663771) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 58197304 + ... + 58197676.

It is an arithmetic number, because the mean of its divisors is an integer number (349895700).

Almost surely, 2^21707663770 is an apocalyptic number.

21707663770 is an abundant number, since it is smaller than the sum of its proper divisors (23078985830).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21707663770 is a wasteful number, since it uses less digits than its factorization.

21707663770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 824.

The product of its (nonzero) digits is 518616, while the sum is 46.

The spelling of 21707663770 in words is "twenty-one billion, seven hundred seven million, six hundred sixty-three thousand, seven hundred seventy".