61287158638 has 4 divisors (see below), whose sum is σ = 91930737960. Its totient is φ = 30643579318.

The previous prime is 61287158623. The next prime is 61287158741. The reversal of 61287158638 is 83685178216.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×61287158638² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15321789658 + ... + 15321789661.

It is an arithmetic number, because the mean of its divisors is an integer number (22982684490).

Almost surely, 2^61287158638 is an apocalyptic number.

61287158638 is a deficient number, since it is larger than the sum of its proper divisors (30643579322).

61287158638 is a wasteful number, since it uses less digits than its factorization.

61287158638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30643579321.

The product of its digits is 3870720, while the sum is 55.

The spelling of 61287158638 in words is "sixty-one billion, two hundred eighty-seven million, one hundred fifty-eight thousand, six hundred thirty-eight".