1115201720 has 32 divisors (see below), whose sum is σ = 2513840400. Its totient is φ = 445256448.

The previous prime is 1115201693. The next prime is 1115201743. The reversal of 1115201720 is 271025111.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1115201692 and 1115201701.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3605 + ... + 47364.

Almost surely, 2^1115201720 is an apocalyptic number.

1115201720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1115201720 is an abundant number, since it is smaller than the sum of its proper divisors (1398638680).

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

1115201720 is a wasteful number, since it uses less digits than its factorization.

1115201720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51527 (or 51523 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 20.

The square root of 1115201720 is about 33394.6360962356. The cubic root of 1115201720 is about 1037.0136593174.

Adding to 1115201720 its reverse (271025111), we get a palindrome (1386226831).

The spelling of 1115201720 in words is "one billion, one hundred fifteen million, two hundred one thousand, seven hundred twenty".