139661401 has 4 divisors (see below), whose sum is σ = 152357904. Its totient is φ = 126964900.

The previous prime is 139661399. The next prime is 139661407. The reversal of 139661401 is 104166931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 139661401 - 2¹ = 139661399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139661407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6348235 + ... + 6348256.

It is an arithmetic number, because the mean of its divisors is an integer number (38089476).

Almost surely, 2^139661401 is an apocalyptic number.

139661401 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

139661401 is a deficient number, since it is larger than the sum of its proper divisors (12696503).

139661401 is a wasteful number, since it uses less digits than its factorization.

139661401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12696502.

The product of its (nonzero) digits is 3888, while the sum is 31.

The square root of 139661401 is about 11817.8424849885. The cubic root of 139661401 is about 518.8304595574.

The spelling of 139661401 in words is "one hundred thirty-nine million, six hundred sixty-one thousand, four hundred one".