1523134721 has 2 divisors, whose sum is σ = 1523134722. Its totient is φ = 1523134720.

The previous prime is 1523134673. The next prime is 1523134733. The reversal of 1523134721 is 1274313251.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1481403121 + 41731600 = 38489^2 + 6460^2 .

It is a cyclic number.

It is not a de Polignac number, because 1523134721 - 2¹⁰ = 1523133697 is a prime.

It is not a weakly prime, because it can be changed into another prime (1523134751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 761567360 + 761567361.

It is an arithmetic number, because the mean of its divisors is an integer number (761567361).

Almost surely, 2^1523134721 is an apocalyptic number.

It is an amenable number.

1523134721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1523134721 is an equidigital number, since it uses as much as digits as its factorization.

1523134721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5040, while the sum is 29.

The square root of 1523134721 is about 39027.3586218694. The cubic root of 1523134721 is about 1150.5692760570.

Adding to 1523134721 its reverse (1274313251), we get a palindrome (2797447972).

The spelling of 1523134721 in words is "one billion, five hundred twenty-three million, one hundred thirty-four thousand, seven hundred twenty-one".