61678437381 has 24 divisors (see below), whose sum is σ = 97247801664. Its totient is φ = 37358741760.

The previous prime is 61678437361. The next prime is 61678437391. The reversal of 61678437381 is 18373487616.

61678437381 is a `hidden beast` number, since 61 + 6 + 78 + 437 + 3 + 81 = 666.

It is not a de Polignac number, because 61678437381 - 2¹⁴ = 61678420997 is a prime.

It is a super-2 number, since 2×61678437381² (a number of 22 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61678437361) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15561 + ... + 351566.

It is an arithmetic number, because the mean of its divisors is an integer number (4051991736).

Almost surely, 2^61678437381 is an apocalyptic number.

It is an amenable number.

61678437381 is a deficient number, since it is larger than the sum of its proper divisors (35569364283).

61678437381 is a wasteful number, since it uses less digits than its factorization.

61678437381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 368841 (or 368838 counting only the distinct ones).

The product of its digits is 4064256, while the sum is 54.

The spelling of 61678437381 in words is "sixty-one billion, six hundred seventy-eight million, four hundred thirty-seven thousand, three hundred eighty-one".