72153999 has 6 divisors (see below), whose sum is σ = 104222456. Its totient is φ = 48102660.

The previous prime is 72153979. The next prime is 72154009. The reversal of 72153999 is 99935127.

It is a happy number.

72153999 is a `hidden beast` number, since 7 + 21 + 539 + 99 = 666.

It is not a de Polignac number, because 72153999 - 2¹⁹ = 71629711 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72153979) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4008547 + ... + 4008564.

Almost surely, 2^72153999 is an apocalyptic number.

72153999 is a deficient number, since it is larger than the sum of its proper divisors (32068457).

72153999 is a wasteful number, since it uses less digits than its factorization.

72153999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8017117 (or 8017114 counting only the distinct ones).

The product of its digits is 153090, while the sum is 45.

The square root of 72153999 is about 8494.3510052269. The cubic root of 72153999 is about 416.3131560151.

The spelling of 72153999 in words is "seventy-two million, one hundred fifty-three thousand, nine hundred ninety-nine".