66907440 has 60 divisors (see below), whose sum is σ = 224699904. Its totient is φ = 17841792.

The previous prime is 66907439. The next prime is 66907453. The reversal of 66907440 is 4470966.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 66907395 and 66907404.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 45744 + ... + 47183.

Almost surely, 2^66907440 is an apocalyptic number.

66907440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66907440 is an abundant number, since it is smaller than the sum of its proper divisors (157792464).

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

66907440 is a wasteful number, since it uses less digits than its factorization.

66907440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92946 (or 92937 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 66907440 is about 8179.6968158973. The cubic root of 66907440 is about 405.9676905704.

It can be divided in two parts, 66 and 907440, that multiplied together give a triangular number (59891040 = T₁₀₉₄₄).

The spelling of 66907440 in words is "sixty-six million, nine hundred seven thousand, four hundred forty".