135121972 has 6 divisors (see below), whose sum is σ = 236463458. Its totient is φ = 67560984.

The previous prime is 135121927. The next prime is 135121979. The reversal of 135121972 is 279121531.

It can be written as a sum of positive squares in only one way, i.e., 69122596 + 65999376 = 8314^2 + 8124^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135121979) 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 as a sum of consecutive naturals, namely, 16890243 + ... + 16890250.

Almost surely, 2^135121972 is an apocalyptic number.

It is an amenable number.

135121972 is a deficient number, since it is larger than the sum of its proper divisors (101341486).

135121972 is a wasteful number, since it uses less digits than its factorization.

135121972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33780497 (or 33780495 counting only the distinct ones).

The product of its digits is 3780, while the sum is 31.

The square root of 135121972 is about 11624.1976927442. The cubic root of 135121972 is about 513.1472331910.

The spelling of 135121972 in words is "one hundred thirty-five million, one hundred twenty-one thousand, nine hundred seventy-two".