915990 has 32 divisors (see below), whose sum is σ = 2315520. Its totient is φ = 231264.

The previous prime is 915973. The next prime is 915991. The reversal of 915990 is 99519.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (915991) by changing a digit.

915990 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 234 + ... + 1373.

It is an arithmetic number, because the mean of its divisors is an integer number (72360).

2⁹¹⁵⁹⁹⁰ is an apocalyptic number.

915990 is an abundant number, since it is smaller than the sum of its proper divisors (1399530).

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

915990 is a wasteful number, since it uses less digits than its factorization.

915990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1636.

The product of its (nonzero) digits is 3645, while the sum is 33.

The square root of 915990 is about 957.0736648764. The cubic root of 915990 is about 97.1173695285.

The spelling of 915990 in words is "nine hundred fifteen thousand, nine hundred ninety".