61851523538 has 16 divisors (see below), whose sum is σ = 112268312064. Its totient is φ = 24948513600.

The previous prime is 61851523499. The next prime is 61851523543. The reversal of 61851523538 is 83532515816.

It is a happy number.

It is a super-2 number, since 2×61851523538² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 61851523492 and 61851523501.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 129939938 + ... + 129940413.

It is an arithmetic number, because the mean of its divisors is an integer number (7016769504).

Almost surely, 2^61851523538 is an apocalyptic number.

61851523538 is a deficient number, since it is larger than the sum of its proper divisors (50416788526).

61851523538 is a wasteful number, since it uses less digits than its factorization.

61851523538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 259880377.

The product of its digits is 864000, while the sum is 47.

The spelling of 61851523538 in words is "sixty-one billion, eight hundred fifty-one million, five hundred twenty-three thousand, five hundred thirty-eight".