139992421 has 8 divisors (see below), whose sum is σ = 146329920. Its totient is φ = 133675872.

The previous prime is 139992407. The next prime is 139992431. The reversal of 139992421 is 124299931.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 139992421 - 2⁵ = 139992389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139992431) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9321 + ... + 19153.

It is an arithmetic number, because the mean of its divisors is an integer number (18291240).

Almost surely, 2^139992421 is an apocalyptic number.

It is an amenable number.

139992421 is a deficient number, since it is larger than the sum of its proper divisors (6337499).

139992421 is an equidigital number, since it uses as much as digits as its factorization.

139992421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10475.

The product of its digits is 34992, while the sum is 40.

The square root of 139992421 is about 11831.8392906598. The cubic root of 139992421 is about 519.2400400368.

The spelling of 139992421 in words is "one hundred thirty-nine million, nine hundred ninety-two thousand, four hundred twenty-one".