21127203904 has 21 divisors (see below), whose sum is σ = 41926602837. Its totient is φ = 10563020544.

The previous prime is 21127203869. The next prime is 21127203943. The reversal of 21127203904 is 40930272112.

The square root of 21127203904 is 145352.

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., 3063843904 + 18063360000 = 55352^2 + 134400^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1153732 + ... + 1171900.

It is an arithmetic number, because the mean of its divisors is an integer number (1996504897).

Almost surely, 2^21127203904 is an apocalyptic number.

21127203904 is the 145352-nd square number.

It is an amenable number.

21127203904 is a deficient number, since it is larger than the sum of its proper divisors (20799398933).

21127203904 is an frugal number, since it uses more digits than its factorization.

21127203904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36350 (or 18171 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The spelling of 21127203904 in words is "twenty-one billion, one hundred twenty-seven million, two hundred three thousand, nine hundred four".