21376465593961 has 27 divisors (see below), whose sum is σ = 21892846813047. Its totient is φ = 20872188453600.

The previous prime is 21376465593953. The next prime is 21376465593997. The reversal of 21376465593961 is 16939556467312.

It is a happy number.

The square root of 21376465593961 is 4623469.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 18487635075625 + 2888830518336 = 4299725^2 + 1699656^2 .

It is not a de Polignac number, because 21376465593961 - 2³ = 21376465593953 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (67).

It is a Duffinian number.

Its product of digits (220449600) is a multiple of the sum of its prime divisors (675).

It is not an unprimeable number, because it can be changed into a prime (21376465593941) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 46775635645 + ... + 46775636101.

It is an arithmetic number, because the mean of its divisors is an integer number (810846178261).

Almost surely, 2^{21376465593961} is an apocalyptic number.

21376465593961 is the 4623469-th square number.

21376465593961 is the 2311735-th centered octagonal number.

It is an amenable number.

21376465593961 is a deficient number, since it is larger than the sum of its proper divisors (516381219086).

21376465593961 is an frugal number, since it uses more digits than its factorization.

21376465593961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1350 (or 675 counting only the distinct ones).

The product of its digits is 220449600, while the sum is 67.

The spelling of 21376465593961 in words is "twenty-one trillion, three hundred seventy-six billion, four hundred sixty-five million, five hundred ninety-three thousand, nine hundred sixty-one".