66156240 has 40 divisors (see below), whose sum is σ = 205085088. Its totient is φ = 17641600.

The previous prime is 66156239. The next prime is 66156283. The reversal of 66156240 is 4265166.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 66156198 and 66156207.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 137586 + ... + 138065.

Almost surely, 2^66156240 is an apocalyptic number.

66156240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66156240 is an abundant number, since it is smaller than the sum of its proper divisors (138928848).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66156240 is a wasteful number, since it uses less digits than its factorization.

66156240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 275667 (or 275661 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 66156240 is about 8133.6486277685. The cubic root of 66156240 is about 404.4426413352.

The spelling of 66156240 in words is "sixty-six million, one hundred fifty-six thousand, two hundred forty".