1225820144 has 20 divisors (see below), whose sum is σ = 2478289296. Its totient is φ = 586261632.

The previous prime is 1225820143. The next prime is 1225820149. The reversal of 1225820144 is 4410285221.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1225820143) 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, 1665149 + ... + 1665884.

Almost surely, 2^1225820144 is an apocalyptic number.

It is an amenable number.

1225820144 is an abundant number, since it is smaller than the sum of its proper divisors (1252469152).

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

1225820144 is a wasteful number, since it uses less digits than its factorization.

1225820144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3331064 (or 3331058 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 29.

The square root of 1225820144 is about 35011.7143824749. The cubic root of 1225820144 is about 1070.2262147270.

The spelling of 1225820144 in words is "one billion, two hundred twenty-five million, eight hundred twenty thousand, one hundred forty-four".