1155904321 has 16 divisors (see below), whose sum is σ = 1373258880. Its totient is φ = 959080320.

The previous prime is 1155904319. The next prime is 1155904327. The reversal of 1155904321 is 1234095511.

It is not a de Polignac number, because 1155904321 - 2¹ = 1155904319 is a prime.

It is a super-2 number, since 2×1155904321² = 2672229598612942082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1155904327) 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, 32685 + ... + 58138.

It is an arithmetic number, because the mean of its divisors is an integer number (85828680).

Almost surely, 2^1155904321 is an apocalyptic number.

1155904321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1155904321 is a deficient number, since it is larger than the sum of its proper divisors (217354559).

1155904321 is a wasteful number, since it uses less digits than its factorization.

1155904321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90936.

The product of its (nonzero) digits is 5400, while the sum is 31.

The square root of 1155904321 is about 33998.5929267668. The cubic root of 1155904321 is about 1049.4795065045.

Adding to 1155904321 its reverse (1234095511), we get a palindrome (2389999832).

It can be divided in two parts, 115590 and 4321, that added together give a palindrome (119911).

The spelling of 1155904321 in words is "one billion, one hundred fifty-five million, nine hundred four thousand, three hundred twenty-one".