165261390 has 32 divisors (see below), whose sum is σ = 453288960. Its totient is φ = 37773984.

The previous prime is 165261389. The next prime is 165261457. The reversal of 165261390 is 93162561.

It is a happy number.

165261390 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×165261390² = 54622654049464200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 393270 + ... + 393689.

It is an arithmetic number, because the mean of its divisors is an integer number (14165280).

Almost surely, 2^165261390 is an apocalyptic number.

165261390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

165261390 is an abundant number, since it is smaller than the sum of its proper divisors (288027570).

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

165261390 is a wasteful number, since it uses less digits than its factorization.

165261390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 786976.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 165261390 is about 12855.4031442036. The cubic root of 165261390 is about 548.7701334622.

The spelling of 165261390 in words is "one hundred sixty-five million, two hundred sixty-one thousand, three hundred ninety".