61523640 has 48 divisors (see below), whose sum is σ = 199953000. Its totient is φ = 16406208.

The previous prime is 61523617. The next prime is 61523647. The reversal of 61523640 is 4632516.

61523640 is a `hidden beast` number, since 6 + 15 + 2 + 3 + 640 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61523647) 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, 85090 + ... + 85809.

Almost surely, 2^61523640 is an apocalyptic number.

61523640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61523640 is an abundant number, since it is smaller than the sum of its proper divisors (138429360).

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

61523640 is a wasteful number, since it uses less digits than its factorization.

61523640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170916 (or 170909 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 61523640 is about 7843.7006572153. The cubic root of 61523640 is about 394.7729079748.

The spelling of 61523640 in words is "sixty-one million, five hundred twenty-three thousand, six hundred forty".