72123051 has 96 divisors (see below), whose sum is σ = 136055808. Its totient is φ = 33384960.

The previous prime is 72123047. The next prime is 72123067. The reversal of 72123051 is 15032127.

It is not a de Polignac number, because 72123051 - 2² = 72123047 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (72123091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 987951 + ... + 988023.

It is an arithmetic number, because the mean of its divisors is an integer number (1417248).

Almost surely, 2^72123051 is an apocalyptic number.

72123051 is a deficient number, since it is larger than the sum of its proper divisors (63932757).

72123051 is a wasteful number, since it uses less digits than its factorization.

72123051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161 (or 154 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 72123051 is about 8492.5291285930. The cubic root of 72123051 is about 416.2536263876.

Adding to 72123051 its reverse (15032127), we get a palindrome (87155178).

The spelling of 72123051 in words is "seventy-two million, one hundred twenty-three thousand, fifty-one".