78772019 has 4 divisors (see below), whose sum is σ = 79293840. Its totient is φ = 78250200.

The previous prime is 78772007. The next prime is 78772061. The reversal of 78772019 is 91027787.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78772019 is a prime.

It is a super-2 number, since 2×78772019² = 12410061954672722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78772069) 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, 260684 + ... + 260985.

It is an arithmetic number, because the mean of its divisors is an integer number (19823460).

Almost surely, 2^78772019 is an apocalyptic number.

78772019 is a deficient number, since it is larger than the sum of its proper divisors (521821).

78772019 is a wasteful number, since it uses less digits than its factorization.

78772019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521820.

The product of its (nonzero) digits is 49392, while the sum is 41.

The square root of 78772019 is about 8875.3602180419. The cubic root of 78772019 is about 428.6708897040.

The spelling of 78772019 in words is "seventy-eight million, seven hundred seventy-two thousand, nineteen".