78121354 has 4 divisors (see below), whose sum is σ = 117182034. Its totient is φ = 39060676.

The previous prime is 78121339. The next prime is 78121387. The reversal of 78121354 is 45312187.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 76090729 + 2030625 = 8723^2 + 1425^2 .

It is a super-2 number, since 2×78121354² = 12205891901586632, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19530337 + ... + 19530340.

Almost surely, 2^78121354 is an apocalyptic number.

78121354 is a deficient number, since it is larger than the sum of its proper divisors (39060680).

78121354 is a wasteful number, since it uses less digits than its factorization.

78121354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39060679.

The product of its digits is 6720, while the sum is 31.

The square root of 78121354 is about 8838.6285135195. The cubic root of 78121354 is about 427.4873363553.

The spelling of 78121354 in words is "seventy-eight million, one hundred twenty-one thousand, three hundred fifty-four".