21663411150164 has 18 divisors (see below), whose sum is σ = 44100515556090. Its totient is φ = 9284319064272.

The previous prime is 21663411150149. The next prime is 21663411150179. The reversal of 21663411150164 is 46105111436612.

It is an interprime number because it is at equal distance from previous prime (21663411150149) and next prime (21663411150179).

It can be written as a sum of positive squares in only one way, i.e., 16169309547664 + 5494101602500 = 4021108^2 + 2343950^2 .

It is a super-2 number, since 2×21663411150164² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 55263803759 + ... + 55263804150.

It is an arithmetic number, because the mean of its divisors is an integer number (2450028642005).

Almost surely, 2^{21663411150164} is an apocalyptic number.

It is an amenable number.

21663411150164 is an abundant number, since it is smaller than the sum of its proper divisors (22437104405926).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21663411150164 is a wasteful number, since it uses less digits than its factorization.

21663411150164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110527607927 (or 110527607918 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 41.

Adding to 21663411150164 its reverse (46105111436612), we get a palindrome (67768522586776).

The spelling of 21663411150164 in words is "twenty-one trillion, six hundred sixty-three billion, four hundred eleven million, one hundred fifty thousand, one hundred sixty-four".