121201020421391 has 4 divisors (see below), whose sum is σ = 121202096088672. Its totient is φ = 121199944754112.

The previous prime is 121201020421343. The next prime is 121201020421499. The reversal of 121201020421391 is 193124020102121.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121201020421391 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 (121201620421391) 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, 537664610 + ... + 537889983.

It is an arithmetic number, because the mean of its divisors is an integer number (30300524022168).

Almost surely, 2^{121201020421391} is an apocalyptic number.

121201020421391 is a deficient number, since it is larger than the sum of its proper divisors (1075667281).

121201020421391 is a wasteful number, since it uses less digits than its factorization.

121201020421391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1075667280.

The product of its (nonzero) digits is 1728, while the sum is 29.

The spelling of 121201020421391 in words is "one hundred twenty-one trillion, two hundred one billion, twenty million, four hundred twenty-one thousand, three hundred ninety-one".