61697640 has 32 divisors (see below), whose sum is σ = 185093280. Its totient is φ = 16452672.

The previous prime is 61697609. The next prime is 61697653. The reversal of 61697640 is 4679616.

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, 256954 + ... + 257193.

It is an arithmetic number, because the mean of its divisors is an integer number (5784165).

Almost surely, 2^61697640 is an apocalyptic number.

61697640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61697640 is an abundant number, since it is smaller than the sum of its proper divisors (123395640).

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

61697640 is a wasteful number, since it uses less digits than its factorization.

61697640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 514161 (or 514157 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 39.

The square root of 61697640 is about 7854.7845291898. The cubic root of 61697640 is about 395.1447207781.

The spelling of 61697640 in words is "sixty-one million, six hundred ninety-seven thousand, six hundred forty".