87778451 has 4 divisors (see below), whose sum is σ = 89217504. Its totient is φ = 86339400.

The previous prime is 87778399. The next prime is 87778487. The reversal of 87778451 is 15487778.

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

It is not a de Polignac number, because 87778451 - 2⁶ = 87778387 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 87778396 and 87778405.

It is not an unprimeable number, because it can be changed into a prime (87778151) 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, 719435 + ... + 719556.

It is an arithmetic number, because the mean of its divisors is an integer number (22304376).

Almost surely, 2^87778451 is an apocalyptic number.

87778451 is a deficient number, since it is larger than the sum of its proper divisors (1439053).

87778451 is a wasteful number, since it uses less digits than its factorization.

87778451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1439052.

The product of its digits is 439040, while the sum is 47.

The square root of 87778451 is about 9369.0154765589. The cubic root of 87778451 is about 444.4224312685.

The spelling of 87778451 in words is "eighty-seven million, seven hundred seventy-eight thousand, four hundred fifty-one".