1263020521 has 9 divisors (see below), whose sum is σ = 1469517399. Its totient is φ = 1082375784.

The previous prime is 1263020513. The next prime is 1263020533. The reversal of 1263020521 is 1250203621.

The square root of 1263020521 is 35539.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1227451225 + 35569296 = 35035^2 + 5964^2 .

It is not a de Polignac number, because 1263020521 - 2³ = 1263020513 is a prime.

It is a super-2 number, since 2×1263020521² = 3190441672934222882, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1263020492 and 1263020501.

It is not an unprimeable number, because it can be changed into a prime (1263020501) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 246235 + ... + 251311.

It is an arithmetic number, because the mean of its divisors is an integer number (163279711).

Almost surely, 2^1263020521 is an apocalyptic number.

1263020521 is the 35539-th square number.

1263020521 is the 17770-th centered octagonal number.

It is an amenable number.

1263020521 is a deficient number, since it is larger than the sum of its proper divisors (206496878).

1263020521 is an frugal number, since it uses more digits than its factorization.

1263020521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10168 (or 5084 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The cubic root of 1263020521 is about 1080.9446812721.

The spelling of 1263020521 in words is "one billion, two hundred sixty-three million, twenty thousand, five hundred twenty-one".