21143907401 has 2 divisors, whose sum is σ = 21143907402. Its totient is φ = 21143907400.

The previous prime is 21143907373. The next prime is 21143907439. The reversal of 21143907401 is 10470934112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20320217401 + 823690000 = 142549^2 + 28700^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143907401 - 2¹⁴ = 21143891017 is a prime.

It is not a weakly prime, because it can be changed into another prime (21143907481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571953700 + 10571953701.

It is an arithmetic number, because the mean of its divisors is an integer number (10571953701).

Almost surely, 2^21143907401 is an apocalyptic number.

It is an amenable number.

21143907401 is a deficient number, since it is larger than the sum of its proper divisors (1).

21143907401 is an equidigital number, since it uses as much as digits as its factorization.

21143907401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6048, while the sum is 32.

The spelling of 21143907401 in words is "twenty-one billion, one hundred forty-three million, nine hundred seven thousand, four hundred one".