21956963501 has 16 divisors (see below), whose sum is σ = 25007391360. Its totient is φ = 19083155520.

The previous prime is 21956963461. The next prime is 21956963503. The reversal of 21956963501 is 10536965912.

It is not a de Polignac number, because 21956963501 - 2¹⁰ = 21956962477 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 (21956963503) 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 15 ways as a sum of consecutive naturals, for example, 491951 + ... + 534723.

It is an arithmetic number, because the mean of its divisors is an integer number (1562961960).

Almost surely, 2^21956963501 is an apocalyptic number.

It is an amenable number.

21956963501 is a deficient number, since it is larger than the sum of its proper divisors (3050427859).

21956963501 is a wasteful number, since it uses less digits than its factorization.

21956963501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44836.

The product of its (nonzero) digits is 437400, while the sum is 47.

It can be divided in two parts, 2195 and 6963501, that added together give a palindrome (6965696).

The spelling of 21956963501 in words is "twenty-one billion, nine hundred fifty-six million, nine hundred sixty-three thousand, five hundred one".