78225649 has 4 divisors (see below), whose sum is σ = 79393264. Its totient is φ = 77058036.

The previous prime is 78225613. The next prime is 78225671. The reversal of 78225649 is 94652287.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 94652287 = 83 ⋅1140389.

It is a cyclic number.

It is not a de Polignac number, because 78225649 - 2⁹ = 78225137 is a prime.

It is a super-2 number, since 2×78225649² = 12238504322942402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78226649) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 583707 + ... + 583840.

It is an arithmetic number, because the mean of its divisors is an integer number (19848316).

Almost surely, 2^78225649 is an apocalyptic number.

It is an amenable number.

78225649 is a deficient number, since it is larger than the sum of its proper divisors (1167615).

78225649 is a wasteful number, since it uses less digits than its factorization.

78225649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1167614.

The product of its digits is 241920, while the sum is 43.

The square root of 78225649 is about 8844.5264994798. The cubic root of 78225649 is about 427.6774890829.

The spelling of 78225649 in words is "seventy-eight million, two hundred twenty-five thousand, six hundred forty-nine".