1915990 has 8 divisors (see below), whose sum is σ = 3448800. Its totient is φ = 766392.

The previous prime is 1915981. The next prime is 1915993. The reversal of 1915990 is 995191.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1915993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 95790 + ... + 95809.

It is an arithmetic number, because the mean of its divisors is an integer number (431100).

2^1915990 is an apocalyptic number.

1915990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1915990 is a deficient number, since it is larger than the sum of its proper divisors (1532810).

1915990 is a wasteful number, since it uses less digits than its factorization.

1915990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191606.

The product of its (nonzero) digits is 3645, while the sum is 34.

The square root of 1915990 is about 1384.1929056313. The cubic root of 1915990 is about 124.2027121351.

It can be divided in two parts, 19 and 15990, that multiplied together give a triangular number (303810 = T₇₇₉).

The spelling of 1915990 in words is "one million, nine hundred fifteen thousand, nine hundred ninety".