1216355250 has 128 divisors (see below), whose sum is σ = 3367713024. Its totient is φ = 289920000.

The previous prime is 1216355249. The next prime is 1216355251. The reversal of 1216355250 is 525536121.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1216355249) and next prime (1216355251).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (1216355251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 502042 + ... + 504458.

It is an arithmetic number, because the mean of its divisors is an integer number (26310258).

Almost surely, 2^1216355250 is an apocalyptic number.

1216355250 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216355250, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1683856512).

1216355250 is an abundant number, since it is smaller than the sum of its proper divisors (2151357774).

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

1216355250 is a wasteful number, since it uses less digits than its factorization.

1216355250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2509 (or 2499 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 30.

The square root of 1216355250 is about 34876.2849225659. The cubic root of 1216355250 is about 1067.4645912198.

The spelling of 1216355250 in words is "one billion, two hundred sixteen million, three hundred fifty-five thousand, two hundred fifty".