1215106840 has 16 divisors (see below), whose sum is σ = 2733990480. Its totient is φ = 486042720.

The previous prime is 1215106811. The next prime is 1215106889. The reversal of 1215106840 is 486015121.

It is a super-2 number, since 2×1215106840² = 2952969265229571200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1215106799 and 1215106808.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15188796 + ... + 15188875.

It is an arithmetic number, because the mean of its divisors is an integer number (170874405).

Almost surely, 2^1215106840 is an apocalyptic number.

1215106840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1215106840 is an abundant number, since it is smaller than the sum of its proper divisors (1518883640).

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

1215106840 is a wasteful number, since it uses less digits than its factorization.

1215106840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30377682 (or 30377678 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 1215106840 is about 34858.3826360318. The cubic root of 1215106840 is about 1067.0992676715.

The spelling of 1215106840 in words is "one billion, two hundred fifteen million, one hundred six thousand, eight hundred forty".