61671640 has 16 divisors (see below), whose sum is σ = 138761280. Its totient is φ = 24668640.

The previous prime is 61671619. The next prime is 61671653. The reversal of 61671640 is 4617616.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 770856 + ... + 770935.

It is an arithmetic number, because the mean of its divisors is an integer number (8672580).

Almost surely, 2^61671640 is an apocalyptic number.

It is an amenable number.

61671640 is an abundant number, since it is smaller than the sum of its proper divisors (77089640).

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

61671640 is a wasteful number, since it uses less digits than its factorization.

61671640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1541802 (or 1541798 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 61671640 is about 7853.1293125734. The cubic root of 61671640 is about 395.0892070057.

The spelling of 61671640 in words is "sixty-one million, six hundred seventy-one thousand, six hundred forty".