1225221400 has 96 divisors (see below), whose sum is σ = 3078084240. Its totient is φ = 450869760.

The previous prime is 1225221397. The next prime is 1225221443. The reversal of 1225221400 is 41225221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1031607 + ... + 1032793.

Almost surely, 2^1225221400 is an apocalyptic number.

1225221400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1225221400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1539042120).

1225221400 is an abundant number, since it is smaller than the sum of its proper divisors (1852862840).

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

1225221400 is a wasteful number, since it uses less digits than its factorization.

1225221400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1613 (or 1604 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 1225221400 is about 35003.1627142463. The cubic root of 1225221400 is about 1070.0519379686.

Adding to 1225221400 its reverse (41225221), we get a palindrome (1266446621).

The spelling of 1225221400 in words is "one billion, two hundred twenty-five million, two hundred twenty-one thousand, four hundred".