1221253488 has 360 divisors, whose sum is σ = 4332901248. Its totient is φ = 314316288.

The previous prime is 1221253477. The next prime is 1221253493. The reversal of 1221253488 is 8843521221.

It is a happy number.

1221253488 is a `hidden beast` number, since 122 + 1 + 2 + 53 + 488 = 666.

It is a super-2 number, since 2×1221253488² = 2982920163904332288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 11413531 + ... + 11413637.

Almost surely, 2^1221253488 is an apocalyptic number.

1221253488 is a gapful number since it is divisible by the number (18) 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 1221253488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2166450624).

1221253488 is an abundant number, since it is smaller than the sum of its proper divisors (3111647760).

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

1221253488 is a wasteful number, since it uses less digits than its factorization.

1221253488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221 (or 199 counting only the distinct ones).

The product of its digits is 30720, while the sum is 36.

The square root of 1221253488 is about 34946.4374149927. The cubic root of 1221253488 is about 1068.8955582194.

The spelling of 1221253488 in words is "one billion, two hundred twenty-one million, two hundred fifty-three thousand, four hundred eighty-eight".