20495121951 has 24 divisors (see below), whose sum is σ = 29068068864. Its totient is φ = 12842277840.

The previous prime is 20495121923. The next prime is 20495121967. The reversal of 20495121951 is 15912159402.

It is a happy number.

It is not a de Polignac number, because 20495121951 - 2¹⁰ = 20495120927 is a prime.

It is a hoax number, since the sum of its digits (39) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20495121151) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63036 + ... + 212046.

It is an arithmetic number, because the mean of its divisors is an integer number (1211169536).

Almost surely, 2^20495121951 is an apocalyptic number.

20495121951 is a deficient number, since it is larger than the sum of its proper divisors (8572946913).

20495121951 is a wasteful number, since it uses less digits than its factorization.

20495121951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149179 (or 149160 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 39.

The spelling of 20495121951 in words is "twenty billion, four hundred ninety-five million, one hundred twenty-one thousand, nine hundred fifty-one".