7423801813721 has 2 divisors, whose sum is σ = 7423801813722. Its totient is φ = 7423801813720.

The previous prime is 7423801813717. The next prime is 7423801813741. The reversal of 7423801813721 is 1273181083247.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5918812645321 + 1504989168400 = 2432861^2 + 1226780^2 .

It is a cyclic number.

It is not a de Polignac number, because 7423801813721 - 2² = 7423801813717 is a prime.

It is a super-2 number, since 2×7423801813721² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7423801813741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3711900906860 + 3711900906861.

It is an arithmetic number, because the mean of its divisors is an integer number (3711900906861).

Almost surely, 2^{7423801813721} is an apocalyptic number.

It is an amenable number.

7423801813721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7423801813721 is an equidigital number, since it uses as much as digits as its factorization.

7423801813721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 451584, while the sum is 47.

Adding to 7423801813721 its reverse (1273181083247), we get a palindrome (8696982896968).

The spelling of 7423801813721 in words is "seven trillion, four hundred twenty-three billion, eight hundred one million, eight hundred thirteen thousand, seven hundred twenty-one".