21120011006077 has 4 divisors (see below), whose sum is σ = 21120023824956. Its totient is φ = 21119998187200.

The previous prime is 21120011006069. The next prime is 21120011006099. The reversal of 21120011006077 is 77060011002112.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10097783645401 + 11022227360676 = 3177701^2 + 3319974^2 .

It is a cyclic number.

It is not a de Polignac number, because 21120011006077 - 2³ = 21120011006069 is a prime.

It is a super-2 number, since 2×21120011006077² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120011001077) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3496924 + ... + 7380277.

It is an arithmetic number, because the mean of its divisors is an integer number (5280005956239).

Almost surely, 2^{21120011006077} is an apocalyptic number.

It is an amenable number.

21120011006077 is a deficient number, since it is larger than the sum of its proper divisors (12818879).

21120011006077 is a wasteful number, since it uses less digits than its factorization.

21120011006077 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12818878.

The product of its (nonzero) digits is 1176, while the sum is 28.

Adding to 21120011006077 its reverse (77060011002112), we get a palindrome (98180022008189).

The spelling of 21120011006077 in words is "twenty-one trillion, one hundred twenty billion, eleven million, six thousand, seventy-seven".