72101989 has 4 divisors (see below), whose sum is σ = 72368320. Its totient is φ = 71835660.

The previous prime is 72101971. The next prime is 72101993. The reversal of 72101989 is 98910127.

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: 98910127 = 4003 ⋅24709.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72101989 is a prime.

It is a super-2 number, since 2×72101989² = 10397393635512242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72101959) 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, 132759 + ... + 133300.

It is an arithmetic number, because the mean of its divisors is an integer number (18092080).

Almost surely, 2^72101989 is an apocalyptic number.

It is an amenable number.

72101989 is a deficient number, since it is larger than the sum of its proper divisors (266331).

72101989 is a wasteful number, since it uses less digits than its factorization.

72101989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 266330.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 72101989 is about 8491.2890069765. The cubic root of 72101989 is about 416.2131031092.

It can be divided in two parts, 7210 and 1989, that multiplied together give a triangular number (14340690 = T₅₃₅₅).

The spelling of 72101989 in words is "seventy-two million, one hundred one thousand, nine hundred eighty-nine".