78961645 has 32 divisors (see below), whose sum is σ = 115458048. Its totient is φ = 50664768.

The previous prime is 78961643. The next prime is 78961657. The reversal of 78961645 is 54616987.

It is not a de Polignac number, because 78961645 - 2¹ = 78961643 is a prime.

It is a super-3 number, since 3×78961645³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a junction number, because it is equal to n+sod(n) for n = 78961595 and 78961604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78961643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 36792 + ... + 38878.

It is an arithmetic number, because the mean of its divisors is an integer number (3608064).

Almost surely, 2^78961645 is an apocalyptic number.

It is an amenable number.

78961645 is a deficient number, since it is larger than the sum of its proper divisors (36496403).

78961645 is a wasteful number, since it uses less digits than its factorization.

78961645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2169.

The product of its digits is 362880, while the sum is 46.

The square root of 78961645 is about 8886.0365180434. The cubic root of 78961645 is about 429.0145904554.

The spelling of 78961645 in words is "seventy-eight million, nine hundred sixty-one thousand, six hundred forty-five".