266390 has 16 divisors (see below), whose sum is σ = 508032. Its totient is φ = 100224.

The previous prime is 266381. The next prime is 266401. The reversal of 266390 is 93662.

It is an Ulam number.

It is a Curzon number.

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, 614 + ... + 953.

It is an arithmetic number, because the mean of its divisors is an integer number (31752).

2²⁶⁶³⁹⁰ is an apocalyptic number.

266390 is a deficient number, since it is larger than the sum of its proper divisors (241642).

266390 is a wasteful number, since it uses less digits than its factorization.

266390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1591.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 266390 is about 516.1298286284. The cubic root of 266390 is about 64.3436913769.

It can be divided in two parts, 266 and 390, that multiplied together give a triangular number (103740 = T₄₅₅).

The spelling of 266390 in words is "two hundred sixty-six thousand, three hundred ninety".