1242215100 has 216 divisors, whose sum is σ = 4472526240. Its totient is φ = 282493440.

The previous prime is 1242215099. The next prime is 1242215111. The reversal of 1242215100 is 15122421.

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

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, 1694334 + ... + 1695066.

It is an arithmetic number, because the mean of its divisors is an integer number (20706140).

Almost surely, 2^1242215100 is an apocalyptic number.

1242215100 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 1242215100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2236263120).

1242215100 is an abundant number, since it is smaller than the sum of its proper divisors (3230311140).

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

1242215100 is a wasteful number, since it uses less digits than its factorization.

1242215100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1029 (or 1019 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 18.

The square root of 1242215100 is about 35245.0719959543. The cubic root of 1242215100 is about 1074.9764119576.

Adding to 1242215100 its reverse (15122421), we get a palindrome (1257337521).

The spelling of 1242215100 in words is "one billion, two hundred forty-two million, two hundred fifteen thousand, one hundred".