1251032220 has 36 divisors (see below), whose sum is σ = 3794798280. Its totient is φ = 333608544.

The previous prime is 1251032207. The next prime is 1251032231. The reversal of 1251032220 is 222301521.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1251032193 and 1251032202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3474910 + ... + 3475269.

Almost surely, 2^1251032220 is an apocalyptic number.

1251032220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1251032220 is an abundant number, since it is smaller than the sum of its proper divisors (2543766060).

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

1251032220 is a wasteful number, since it uses less digits than its factorization.

1251032220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6950194 (or 6950189 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 1251032220 is about 35369.9338421773. The cubic root of 1251032220 is about 1077.5137768456.

Adding to 1251032220 its reverse (222301521), we get a palindrome (1473333741).

The spelling of 1251032220 in words is "one billion, two hundred fifty-one million, thirty-two thousand, two hundred twenty".