21351251301272 has 32 divisors (see below), whose sum is σ = 42258011040000. Its totient is φ = 10085578583328.

The previous prime is 21351251301269. The next prime is 21351251301299. The reversal of 21351251301272 is 27210315215312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 195584372 + ... + 195693507.

It is an arithmetic number, because the mean of its divisors is an integer number (1320562845000).

Almost surely, 2^{21351251301272} is an apocalyptic number.

It is an amenable number.

21351251301272 is a deficient number, since it is larger than the sum of its proper divisors (20906759738728).

21351251301272 is a wasteful number, since it uses less digits than its factorization.

21351251301272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391278263 (or 391278259 counting only the distinct ones).

The product of its (nonzero) digits is 25200, while the sum is 35.

Adding to 21351251301272 its reverse (27210315215312), we get a palindrome (48561566516584).

The spelling of 21351251301272 in words is "twenty-one trillion, three hundred fifty-one billion, two hundred fifty-one million, three hundred one thousand, two hundred seventy-two".