72428641 has 4 divisors (see below), whose sum is σ = 74113072. Its totient is φ = 70744212.

The previous prime is 72428623. The next prime is 72428659. The reversal of 72428641 is 14682427.

It is a happy number.

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: 14682427 = 137 ⋅107171.

It is an interprime number because it is at equal distance from previous prime (72428623) and next prime (72428659).

It is a cyclic number.

It is not a de Polignac number, because 72428641 - 2²¹ = 70331489 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72428597 and 72428606.

It is not an unprimeable number, because it can be changed into a prime (72428611) 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, 842151 + ... + 842236.

It is an arithmetic number, because the mean of its divisors is an integer number (18528268).

Almost surely, 2^72428641 is an apocalyptic number.

It is an amenable number.

72428641 is a deficient number, since it is larger than the sum of its proper divisors (1684431).

72428641 is a wasteful number, since it uses less digits than its factorization.

72428641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1684430.

The product of its digits is 21504, while the sum is 34.

The square root of 72428641 is about 8510.5018065917. The cubic root of 72428641 is about 416.8406958009.

The spelling of 72428641 in words is "seventy-two million, four hundred twenty-eight thousand, six hundred forty-one".