1251622720 has 112 divisors (see below), whose sum is σ = 3161995200. Its totient is φ = 470568960.

The previous prime is 1251622711. The next prime is 1251622733. The reversal of 1251622720 is 272261521.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 844380 + ... + 845860.

It is an arithmetic number, because the mean of its divisors is an integer number (28232100).

Almost surely, 2^1251622720 is an apocalyptic number.

1251622720 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 1251622720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1580997600).

1251622720 is an abundant number, since it is smaller than the sum of its proper divisors (1910372480).

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

1251622720 is a wasteful number, since it uses less digits than its factorization.

1251622720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1656 (or 1646 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 1251622720 is about 35378.2803426057. The cubic root of 1251622720 is about 1077.6832826857.

The spelling of 1251622720 in words is "one billion, two hundred fifty-one million, six hundred twenty-two thousand, seven hundred twenty".