1523720707021 has 2 divisors, whose sum is σ = 1523720707022. Its totient is φ = 1523720707020.

The previous prime is 1523720707013. The next prime is 1523720707037. The reversal of 1523720707021 is 1207070273251.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1480711754025 + 43008952996 = 1216845^2 + 207386^2 .

It is an emirp because it is prime and its reverse (1207070273251) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1523720707021 - 2³ = 1523720707013 is a prime.

It is a super-2 number, since 2×1523720707021² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1523720707081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 761860353510 + 761860353511.

It is an arithmetic number, because the mean of its divisors is an integer number (761860353511).

Almost surely, 2^{1523720707021} is an apocalyptic number.

It is an amenable number.

1523720707021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1523720707021 is an equidigital number, since it uses as much as digits as its factorization.

1523720707021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41160, while the sum is 37.

The spelling of 1523720707021 in words is "one trillion, five hundred twenty-three billion, seven hundred twenty million, seven hundred seven thousand, twenty-one".