111621399 has 16 divisors (see below), whose sum is σ = 151656960. Its totient is φ = 73006560.

The previous prime is 111621379. The next prime is 111621403. The reversal of 111621399 is 993126111.

It is not a de Polignac number, because 111621399 - 2⁷ = 111621271 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111621329) 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, 132622 + ... + 133460.

It is an arithmetic number, because the mean of its divisors is an integer number (9478560).

Almost surely, 2^111621399 is an apocalyptic number.

111621399 is a deficient number, since it is larger than the sum of its proper divisors (40035561).

111621399 is an equidigital number, since it uses as much as digits as its factorization.

111621399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1630.

The product of its digits is 2916, while the sum is 33.

The square root of 111621399 is about 10565.1028863897. The cubic root of 111621399 is about 481.4846954652.

It can be divided in two parts, 11162 and 1399, that added together give a triangular number (12561 = T₁₅₈).

The spelling of 111621399 in words is "one hundred eleven million, six hundred twenty-one thousand, three hundred ninety-nine".