20011231402 has 4 divisors (see below), whose sum is σ = 30016847106. Its totient is φ = 10005615700.

The previous prime is 20011231399. The next prime is 20011231447. The reversal of 20011231402 is 20413211002.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 20413211002 = 2 ⋅10206605501.

It can be written as a sum of positive squares in only one way, i.e., 14111301681 + 5899929721 = 118791^2 + 76811^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5002807849 + ... + 5002807852.

Almost surely, 2^20011231402 is an apocalyptic number.

20011231402 is a deficient number, since it is larger than the sum of its proper divisors (10005615704).

20011231402 is a wasteful number, since it uses less digits than its factorization.

20011231402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10005615703.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 20011231402 its reverse (20413211002), we get a palindrome (40424442404).

The spelling of 20011231402 in words is "twenty billion, eleven million, two hundred thirty-one thousand, four hundred two".