21070651607 has 4 divisors (see below), whose sum is σ = 21095354280. Its totient is φ = 21045948936.

The previous prime is 21070651577. The next prime is 21070651619. The reversal of 21070651607 is 70615607012.

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

It is a cyclic number.

It is not a de Polignac number, because 21070651607 - 2¹⁶ = 21070586071 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21070651807) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12350057 + ... + 12351762.

It is an arithmetic number, because the mean of its divisors is an integer number (5273838570).

Almost surely, 2^21070651607 is an apocalyptic number.

21070651607 is a deficient number, since it is larger than the sum of its proper divisors (24702673).

21070651607 is an equidigital number, since it uses as much as digits as its factorization.

21070651607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24702672.

The product of its (nonzero) digits is 17640, while the sum is 35.

The spelling of 21070651607 in words is "twenty-one billion, seventy million, six hundred fifty-one thousand, six hundred seven".