13770521 has 4 divisors (see below), whose sum is σ = 13964544. Its totient is φ = 13576500.

The previous prime is 13770511. The next prime is 13770529. The reversal of 13770521 is 12507731.

13770521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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: 12507731 = 3083 ⋅4057.

It is a cyclic number.

It is not a de Polignac number, because 13770521 - 2¹⁸ = 13508377 is a prime.

It is a super-2 number, since 2×13770521² = 379254497222882, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13770529) 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, 96905 + ... + 97046.

It is an arithmetic number, because the mean of its divisors is an integer number (3491136).

Almost surely, 2^13770521 is an apocalyptic number.

It is an amenable number.

13770521 is a deficient number, since it is larger than the sum of its proper divisors (194023).

13770521 is an equidigital number, since it uses as much as digits as its factorization.

13770521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194022.

The product of its (nonzero) digits is 1470, while the sum is 26.

The square root of 13770521 is about 3710.8652629811. The cubic root of 13770521 is about 239.6901150991.

The spelling of 13770521 in words is "thirteen million, seven hundred seventy thousand, five hundred twenty-one".