139187961 has 12 divisors (see below), whose sum is σ = 219326640. Its totient is φ = 84356280.

The previous prime is 139187957. The next prime is 139188013. The reversal of 139187961 is 169781931.

It is not a de Polignac number, because 139187961 - 2² = 139187957 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139187261) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 702871 + ... + 703068.

It is an arithmetic number, because the mean of its divisors is an integer number (18277220).

Almost surely, 2^139187961 is an apocalyptic number.

139187961 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

139187961 is a deficient number, since it is larger than the sum of its proper divisors (80138679).

139187961 is a wasteful number, since it uses less digits than its factorization.

139187961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1405956 (or 1405953 counting only the distinct ones).

The product of its digits is 81648, while the sum is 45.

The square root of 139187961 is about 11797.7947515627. The cubic root of 139187961 is about 518.2435324717.

The spelling of 139187961 in words is "one hundred thirty-nine million, one hundred eighty-seven thousand, nine hundred sixty-one".