1215111450 has 96 divisors (see below), whose sum is σ = 3537166464. Its totient is φ = 270224640.

The previous prime is 1215111439. The next prime is 1215111479. The reversal of 1215111450 is 541115121.

It is a super-2 number, since 2×1215111450² = 2952991671842205000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 23212 + ... + 54488.

It is an arithmetic number, because the mean of its divisors is an integer number (36845484).

Almost surely, 2^1215111450 is an apocalyptic number.

1215111450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1215111450, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1768583232).

1215111450 is an abundant number, since it is smaller than the sum of its proper divisors (2322055014).

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

1215111450 is a wasteful number, since it uses less digits than its factorization.

1215111450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31336 (or 31331 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 21.

The square root of 1215111450 is about 34858.4487606663. The cubic root of 1215111450 is about 1067.1006171609.

Adding to 1215111450 its reverse (541115121), we get a palindrome (1756226571).

The spelling of 1215111450 in words is "one billion, two hundred fifteen million, one hundred eleven thousand, four hundred fifty".