21364064553 has 16 divisors (see below), whose sum is σ = 30747476480. Its totient is φ = 13116743424.

The previous prime is 21364064539. The next prime is 21364064567. The reversal of 21364064553 is 35546046312.

It is an interprime number because it is at equal distance from previous prime (21364064539) and next prime (21364064567).

It is not a de Polignac number, because 21364064553 - 2⁶ = 21364064489 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21364064593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 615673 + ... + 649446.

It is an arithmetic number, because the mean of its divisors is an integer number (1921717280).

Almost surely, 2^21364064553 is an apocalyptic number.

It is an amenable number.

21364064553 is a deficient number, since it is larger than the sum of its proper divisors (9383411927).

21364064553 is a wasteful number, since it uses less digits than its factorization.

21364064553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1265568.

The product of its (nonzero) digits is 259200, while the sum is 39.

The spelling of 21364064553 in words is "twenty-one billion, three hundred sixty-four million, sixty-four thousand, five hundred fifty-three".