21364720437464 has 8 divisors (see below), whose sum is σ = 40058850820260. Its totient is φ = 10682360218728.

The previous prime is 21364720437461. The next prime is 21364720437497. The reversal of 21364720437464 is 46473402746312.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21364720437461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1335295027334 + ... + 1335295027349.

Almost surely, 2^{21364720437464} is an apocalyptic number.

It is an amenable number.

21364720437464 is a deficient number, since it is larger than the sum of its proper divisors (18694130382796).

21364720437464 is a wasteful number, since it uses less digits than its factorization.

21364720437464 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2670590054689 (or 2670590054685 counting only the distinct ones).

The product of its (nonzero) digits is 16257024, while the sum is 53.

The spelling of 21364720437464 in words is "twenty-one trillion, three hundred sixty-four billion, seven hundred twenty million, four hundred thirty-seven thousand, four hundred sixty-four".