20942609940 has 336 divisors, whose sum is σ = 75896940672. Its totient is φ = 4752753408.

The previous prime is 20942609923. The next prime is 20942609981. The reversal of 20942609940 is 4990624902.

It is a happy number.

It is a super-2 number, since 2×20942609940² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 111 ways as a sum of consecutive naturals, for example, 16022767 + ... + 16024073.

It is an arithmetic number, because the mean of its divisors is an integer number (225883752).

Almost surely, 2^20942609940 is an apocalyptic number.

20942609940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20942609940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37948470336).

20942609940 is an abundant number, since it is smaller than the sum of its proper divisors (54954330732).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20942609940 is a wasteful number, since it uses less digits than its factorization.

20942609940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1498 (or 1481 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The spelling of 20942609940 in words is "twenty billion, nine hundred forty-two million, six hundred nine thousand, nine hundred forty".