247621 has 4 divisors (see below), whose sum is σ = 270144. Its totient is φ = 225100.

The previous prime is 247613. The next prime is 247633. The reversal of 247621 is 126742.

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.

It is a cyclic number.

It is not a de Polignac number, because 247621 - 2³ = 247613 is a prime.

It is a super-2 number, since 2×247621² = 122632319282, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 247592 and 247601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (247601) 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, 11245 + ... + 11266.

It is an arithmetic number, because the mean of its divisors is an integer number (67536).

2²⁴⁷⁶²¹ is an apocalyptic number.

It is an amenable number.

247621 is a deficient number, since it is larger than the sum of its proper divisors (22523).

247621 is a wasteful number, since it uses less digits than its factorization.

247621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22522.

The product of its digits is 672, while the sum is 22.

The square root of 247621 is about 497.6153132692. The cubic root of 247621 is about 62.7955918038.

It can be divided in two parts, 247 and 621, that added together give a palindrome (868).

The spelling of 247621 in words is "two hundred forty-seven thousand, six hundred twenty-one".