78121101 has 8 divisors (see below), whose sum is σ = 104707584. Its totient is φ = 51807680.

The previous prime is 78121093. The next prime is 78121111. The reversal of 78121101 is 10112187.

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

It is a cyclic number.

It is not a de Polignac number, because 78121101 - 2³ = 78121093 is a prime.

It is a super-2 number, since 2×78121101² = 12205812842904402, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78121111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67596 + ... + 68741.

It is an arithmetic number, because the mean of its divisors is an integer number (13088448).

Almost surely, 2^78121101 is an apocalyptic number.

It is an amenable number.

78121101 is a deficient number, since it is larger than the sum of its proper divisors (26586483).

78121101 is a wasteful number, since it uses less digits than its factorization.

78121101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136531.

The product of its (nonzero) digits is 112, while the sum is 21.

The square root of 78121101 is about 8838.6142013327. The cubic root of 78121101 is about 427.4868748749.

Adding to 78121101 its reverse (10112187), we get a palindrome (88233288).

The spelling of 78121101 in words is "seventy-eight million, one hundred twenty-one thousand, one hundred one".