1215453666 has 32 divisors (see below), whose sum is σ = 2781204480. Its totient is φ = 346894416.

The previous prime is 1215453661. The next prime is 1215453677. The reversal of 1215453666 is 6663545121.

It is a super-2 number, since 2×1215453666² = 2954655228385679112, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1215453661) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24495 + ... + 55053.

It is an arithmetic number, because the mean of its divisors is an integer number (86912640).

Almost surely, 2^1215453666 is an apocalyptic number.

1215453666 is an abundant number, since it is smaller than the sum of its proper divisors (1565750814).

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

1215453666 is a wasteful number, since it uses less digits than its factorization.

1215453666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31518.

The product of its digits is 129600, while the sum is 39.

The square root of 1215453666 is about 34863.3570672705. The cubic root of 1215453666 is about 1067.2007848253.

Adding to 1215453666 its reverse (6663545121), we get a palindrome (7878998787).

The spelling of 1215453666 in words is "one billion, two hundred fifteen million, four hundred fifty-three thousand, six hundred sixty-six".