72437981 has 12 divisors (see below), whose sum is σ = 90997536. Its totient is φ = 56444520.

The previous prime is 72437957. The next prime is 72437999. The reversal of 72437981 is 18973427.

72437981 = T₁₃₃₃ + T₁₃₃₄ + ... + T₁₄₀₉.

It is a de Polignac number, because none of the positive numbers 2^k-72437981 is a prime.

It is a super-2 number, since 2×72437981² = 10494522182712722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72437381) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 41915 + ... + 43608.

It is an arithmetic number, because the mean of its divisors is an integer number (7583128).

Almost surely, 2^72437981 is an apocalyptic number.

It is an amenable number.

72437981 is a deficient number, since it is larger than the sum of its proper divisors (18559555).

72437981 is a wasteful number, since it uses less digits than its factorization.

72437981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85552 (or 85541 counting only the distinct ones).

The product of its digits is 84672, while the sum is 41.

The square root of 72437981 is about 8511.0505227028. The cubic root of 72437981 is about 416.8586128602.

The spelling of 72437981 in words is "seventy-two million, four hundred thirty-seven thousand, nine hundred eighty-one".