263121013 has 4 divisors (see below), whose sum is σ = 265192960. Its totient is φ = 261049068.

The previous prime is 263120983. The next prime is 263121029. The reversal of 263121013 is 310121362.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 310121362 = 2 ⋅155060681.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-263121013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (263121043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1035783 + ... + 1036036.

It is an arithmetic number, because the mean of its divisors is an integer number (66298240).

Almost surely, 2^263121013 is an apocalyptic number.

It is an amenable number.

263121013 is a deficient number, since it is larger than the sum of its proper divisors (2071947).

263121013 is a wasteful number, since it uses less digits than its factorization.

263121013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2071946.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 263121013 is about 16221.0053017684. The cubic root of 263121013 is about 640.7941094794.

Adding to 263121013 its reverse (310121362), we get a palindrome (573242375).

The spelling of 263121013 in words is "two hundred sixty-three million, one hundred twenty-one thousand, thirteen".