21264602745 has 32 divisors (see below), whose sum is σ = 36615335040. Its totient is φ = 10499005440.

The previous prime is 21264602743. The next prime is 21264602747. The reversal of 21264602745 is 54720646212.

It is an interprime number because it is at equal distance from previous prime (21264602743) and next prime (21264602747).

It is not a de Polignac number, because 21264602745 - 2¹ = 21264602743 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21264602743) 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 31 ways as a sum of consecutive naturals, for example, 667975 + ... + 699084.

It is an arithmetic number, because the mean of its divisors is an integer number (1144229220).

Almost surely, 2^21264602745 is an apocalyptic number.

It is an amenable number.

21264602745 is a deficient number, since it is larger than the sum of its proper divisors (15350732295).

21264602745 is a wasteful number, since it uses less digits than its factorization.

21264602745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1367145.

The product of its (nonzero) digits is 161280, while the sum is 39.

The spelling of 21264602745 in words is "twenty-one billion, two hundred sixty-four million, six hundred two thousand, seven hundred forty-five".