612121220 has 24 divisors (see below), whose sum is σ = 1286640600. Its totient is φ = 244622592.

The previous prime is 612121201. The next prime is 612121231. The reversal of 612121220 is 22121216.

It can be written as a sum of positive squares in 4 ways, for example, as 350464 + 611770756 = 592^2 + 24734^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9026 + ... + 36134.

It is an arithmetic number, because the mean of its divisors is an integer number (53610025).

Almost surely, 2^612121220 is an apocalyptic number.

It is an amenable number.

612121220 is an abundant number, since it is smaller than the sum of its proper divisors (674519380).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

612121220 is a wasteful number, since it uses less digits than its factorization.

612121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28247 (or 28245 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 612121220 is about 24741.0836464372. The cubic root of 612121220 is about 849.0745267431.

Adding to 612121220 its reverse (22121216), we get a palindrome (634242436).

The spelling of 612121220 in words is "six hundred twelve million, one hundred twenty-one thousand, two hundred twenty".