137661220 has 24 divisors (see below), whose sum is σ = 289812600. Its totient is φ = 54926592.

The previous prime is 137661191. The next prime is 137661221. The reversal of 137661220 is 22166731.

It can be written as a sum of positive squares in 4 ways, for example, as 8020224 + 129640996 = 2832^2 + 11386^2 .

It is a super-2 number, since 2×137661220² = 37901222983776800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (137661221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 235 + ... + 16594.

It is an arithmetic number, because the mean of its divisors is an integer number (12075525).

Almost surely, 2^137661220 is an apocalyptic number.

137661220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

137661220 is an abundant number, since it is smaller than the sum of its proper divisors (152151380).

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

137661220 is a wasteful number, since it uses less digits than its factorization.

It is an anagram of its base 9 representation: 137661220 = (317026621)₉.

137661220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17247 (or 17245 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 137661220 is about 11732.9118295502. The cubic root of 137661220 is about 516.3417052408.

The spelling of 137661220 in words is "one hundred thirty-seven million, six hundred sixty-one thousand, two hundred twenty".