20402120101 has 4 divisors (see below), whose sum is σ = 22256858304. Its totient is φ = 18547381900.

The previous prime is 20402120093. The next prime is 20402120111. The reversal of 20402120101 is 10102120402.

It is a happy number.

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 20402120101 - 2³ = 20402120093 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 (20402120111) 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, 927369085 + ... + 927369106.

It is an arithmetic number, because the mean of its divisors is an integer number (5564214576).

Almost surely, 2^20402120101 is an apocalyptic number.

It is an amenable number.

20402120101 is a deficient number, since it is larger than the sum of its proper divisors (1854738203).

20402120101 is a wasteful number, since it uses less digits than its factorization.

20402120101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1854738202.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 20402120101 its reverse (10102120402), we get a palindrome (30504240503).

The spelling of 20402120101 in words is "twenty billion, four hundred two million, one hundred twenty thousand, one hundred one".