72401387 has 4 divisors (see below), whose sum is σ = 72549336. Its totient is φ = 72253440.

The previous prime is 72401377. The next prime is 72401389. The reversal of 72401387 is 78310427.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78310427 = 13 ⋅6023879.

It is a cyclic number.

It is not a de Polignac number, because 72401387 - 2⁶ = 72401323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72401389) 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, 73238 + ... + 74219.

It is an arithmetic number, because the mean of its divisors is an integer number (18137334).

Almost surely, 2^72401387 is an apocalyptic number.

72401387 is a deficient number, since it is larger than the sum of its proper divisors (147949).

72401387 is a wasteful number, since it uses less digits than its factorization.

72401387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147948.

The product of its (nonzero) digits is 9408, while the sum is 32.

The square root of 72401387 is about 8508.9004577560. The cubic root of 72401387 is about 416.7884052456.

The spelling of 72401387 in words is "seventy-two million, four hundred one thousand, three hundred eighty-seven".