1221551562 has 64 divisors (see below), whose sum is σ = 3084595200. Its totient is φ = 313260480.

The previous prime is 1221551561. The next prime is 1221551563. The reversal of 1221551562 is 2651551221.

1221551562 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (1221551561) and next prime (1221551563).

It is not an unprimeable number, because it can be changed into a prime (1221551561) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19764 + ... + 53232.

It is an arithmetic number, because the mean of its divisors is an integer number (48196800).

Almost surely, 2^1221551562 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221551562, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1542297600).

1221551562 is an abundant number, since it is smaller than the sum of its proper divisors (1863043638).

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

1221551562 is a wasteful number, since it uses less digits than its factorization.

1221551562 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33571.

The product of its digits is 6000, while the sum is 30.

The square root of 1221551562 is about 34950.7018813643. The cubic root of 1221551562 is about 1068.9825137013.

The spelling of 1221551562 in words is "one billion, two hundred twenty-one million, five hundred fifty-one thousand, five hundred sixty-two".