72156019 has 4 divisors (see below), whose sum is σ = 77706496. Its totient is φ = 66605544.

The previous prime is 72156017. The next prime is 72156059. The reversal of 72156019 is 91065127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 91065127 = 67 ⋅1359181.

It is a cyclic number.

It is not a de Polignac number, because 72156019 - 2¹ = 72156017 is a prime.

It is a super-2 number, since 2×72156019² = 10412982155856722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72156011) 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, 2775219 + ... + 2775244.

It is an arithmetic number, because the mean of its divisors is an integer number (19426624).

Almost surely, 2^72156019 is an apocalyptic number.

72156019 is a deficient number, since it is larger than the sum of its proper divisors (5550477).

72156019 is a wasteful number, since it uses less digits than its factorization.

72156019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5550476.

The product of its (nonzero) digits is 3780, while the sum is 31.

The square root of 72156019 is about 8494.4699069453. The cubic root of 72156019 is about 416.3170409683.

The spelling of 72156019 in words is "seventy-two million, one hundred fifty-six thousand, nineteen".