21864254505 has 32 divisors (see below), whose sum is σ = 36054036480. Its totient is φ = 11307764160.

The previous prime is 21864254501. The next prime is 21864254527. The reversal of 21864254505 is 50545246812.

It is not a de Polignac number, because 21864254505 - 2² = 21864254501 is a prime.

It is a super-3 number, since 3×21864254505³ (a number of 32 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21864254501) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32281 + ... + 211590.

It is an arithmetic number, because the mean of its divisors is an integer number (1126688640).

Almost surely, 2^21864254505 is an apocalyptic number.

It is an amenable number.

21864254505 is a deficient number, since it is larger than the sum of its proper divisors (14189781975).

21864254505 is a wasteful number, since it uses less digits than its factorization.

21864254505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 244061.

The product of its (nonzero) digits is 384000, while the sum is 42.

The spelling of 21864254505 in words is "twenty-one billion, eight hundred sixty-four million, two hundred fifty-four thousand, five hundred five".