21077110634 has 4 divisors (see below), whose sum is σ = 31615665954. Its totient is φ = 10538555316.

The previous prime is 21077110631. The next prime is 21077110667. The reversal of 21077110634 is 43601177012.

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

It can be written as a sum of positive squares in only one way, i.e., 15733939225 + 5343171409 = 125435^2 + 73097^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21077110634.

It is not an unprimeable number, because it can be changed into a prime (21077110631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5269277657 + ... + 5269277660.

Almost surely, 2^21077110634 is an apocalyptic number.

21077110634 is a deficient number, since it is larger than the sum of its proper divisors (10538555320).

21077110634 is a wasteful number, since it uses less digits than its factorization.

21077110634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10538555319.

The product of its (nonzero) digits is 7056, while the sum is 32.

Adding to 21077110634 its reverse (43601177012), we get a palindrome (64678287646).

The spelling of 21077110634 in words is "twenty-one billion, seventy-seven million, one hundred ten thousand, six hundred thirty-four".