61224209 has 4 divisors (see below), whose sum is σ = 61266240. Its totient is φ = 61182180.

The previous prime is 61224199. The next prime is 61224211. The reversal of 61224209 is 90242216.

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 61224209 - 2¹² = 61220113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61224239) 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, 18749 + ... + 21770.

It is an arithmetic number, because the mean of its divisors is an integer number (15316560).

Almost surely, 2^61224209 is an apocalyptic number.

It is an amenable number.

61224209 is a deficient number, since it is larger than the sum of its proper divisors (42031).

61224209 is a wasteful number, since it uses less digits than its factorization.

61224209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42030.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 61224209 is about 7824.5900212088. The cubic root of 61224209 is about 394.1314226561.

The spelling of 61224209 in words is "sixty-one million, two hundred twenty-four thousand, two hundred nine".